EP2606288B1 - Central receiver solar system comprising a heliostat field and process to install a field of heliostats of such a system - Google Patents

Description

The invention relates to methods for designing a heliostat field of a solar Zentralreceiversystems and a solar Zentralreceiversystem with a heliostat field consisting of one or more receivers, a plurality of heliostat data forming the heliostat, which are arranged on a preferably flat overall surface, wherein the heliostat one by two axes of rotation adjustable reflector, which reflects the solar radiation to the target surface of the one or more receivers with changing position of the sun, wherein the target surface is the aperture, the thermal absorber or the photovoltaic absorber of the respective receiver, wherein the heliostat a first axis of rotation and one to the first vertical second axis of rotation, which is arranged on a footprint, wherein the first axis of rotation with respect to the footprint and the second axis of rotation with respect to the reflector are fixed, and a support structure, on which one or several receivers are mounted above in relation to the earth's surface of the heliostat field.

State of the art

In the following, the basic function of known solar tower power plants or solar tower systems on the basis of Fig. 1 to Fig. 6 explained.

In Fig. 1 is one out US 4,172,443 known solar tower power plant or solar tower system shown having a tower 120 on which a receiver 110 is installed, focus on the heliostat 190 solar radiation. The heliostat field 130 consists of a plurality of such heliostats 190. In other known towers even multiple receivers may be installed on a tower, as in FIG EP 2000669 A2 shown. As shown in [1] - especially on pages 237ff -, the concentrated radiation through the receiver heats a heat transfer medium, by which a turbine is driven, which then generates electricity via a mechanically coupled generator.

1. 1. Solarturmsystem mit umgebendem Heliostatenfeld (Fernfeld), siehe Prinzipdarstellung einer Draufsicht in Fig. 2.
2. 2. Solarturmsystem mit Polarfeld, siehe Prinzipdarstellung einer Draufsicht in Fig. 3.
3. 3. Solarturmsystem mit Heliostatenfeld unterhalb des Receivers (Nahfeld), siehe Prinzipdarstellung einer Draufsicht in Fig. 4 und in perspektivischer Sicht in Fig. 5.
4. 4. Solarturmsystem mit Nord- und Südfeld, siehe Prinzipdarstellung einer Draufsicht in Fig. 6.

Solar tower systems known today can be classified and characterized as follows in four solar tower systems:

1. 1. Solar tower system with surrounding heliostat field (far field), see schematic diagram of a plan view in Fig. 2 ,
2. 2. Solar tower system with polar field, see schematic diagram of a plan view in Fig. 3 ,
3. 3. Solar tower system with heliostat field below the receiver (near field), see schematic diagram of a plan view in Fig. 4 and in perspective view in Fig. 5 ,
4. 4. Solar tower system with north and south field, see schematic diagram of a plan view in Fig. 6 ,

The mentioned the Fig. 2 to Fig. 6 will be described in more detail below.

1. Solar tower systems with surrounding heliostat field (far field)

Most (commercial) solar tower systems consist of a cylindrical or upside-down frusto-conical receiver oriented 360 degrees in all directions and supported by a central tower surrounded by a heliostat array 130 formed of individual heliostat 190, as in FIG Fig. 1 and as a top view in Fig. 2 shown. A cylindrical receiver or an upside-down truncated cone-shaped receiver are receivers with an external absorber, in which the outer surface of the receiver forms the absorber surface. In Fig. 1 is one out US 4,172,443 known solar tower system, in which a cylindrical receiver 110, whose cylindrical outer surface forms the absorber surface, is arranged on a tower 120 in a receiver height H _R above the heliostat field 130.

Fig. 2 shows the schematic diagram of a plan view of a known solar tower system with the tower 210 in the surrounding surrounding heliostat data field 230. The heliostat data field 230 has the shape of a ring in which the region 234 in the vicinity of the receiver 210 supporting tower 220 is free, ie that in the region 234 no heliostats are arranged. The position of the tower with the receiver is often not exactly central, but is shifted in the direction of the heliostat field towards the equator, ie in the northern hemisphere of the earth to the south or in the southern hemisphere of the earth to the north.

mit dem größer werdenden Abstand vom Receiver abnimmt. Die Reflektorflächendichte

ist definiert als das Verhältnis der Reflektorfläche des Heliostatenfeldes zur Grundfläche des Heliostatenfeldes. In Fig. 2 ist die Region 234 nahe am Receiver 210, in der keine Heliostaten installiert sind, dargestellt.at Fig. 2 the heliostat field consists of a far field. The far field is a heliostat field - which, in contrast to the near field defined below, surrounds the tower and the receiver with a certain horizontal distance, and its reflector surface density

decreases with the increasing distance from the receiver. The reflector surface density

is defined as the ratio of the reflector area of the heliostat field to the base area of the heliostat field. In Fig. 2 For example, region 234 is shown near receiver 210 where no heliostats are installed.

The receiver may be, instead of being continuously cylindrical or continuously frusto-conical, i.a. also consist of a plurality of individual receivers.

The receiver height H _R is as in Fig. 1 Shown as defined as the vertical distance of the center of the absorber surface of an external absorber receiver or the receiver aperture of a cavity receiver from the plane defined by the centers of the reflectors of the heliostat of the heliostat array. The receiver height H _R is hereafter used as a unit size at which other quantities, such as the heliostat field size, are sized.

The diameter D _{H of} a heliostat field is, as in the Fig. 2 . 3 . 4 and 6 shown as the distance, the most distant heliostat.

Solar tower systems with surrounding heliostat field typically have receiver heights H _R of over 100 m and heliostat fields with a diameter of more than eight receiver heights, ie D _H > 8 × H _R. For example, the Gemasolar solar tower described in [2] has a receiver height H _R of 140 m and a diameter D _H of approximately 1,200 m. For example, the Solar-Reserve solar tower described in [3] has a receiver height H _R = 182.88 m (600 feet) and D _H = 2600 m.

2. Solar tower systems with polar field

As in the schematic representation of the plan view of a solar tower system with polar field in Fig. 3 see, this has a heliostat field 330 only on the polar side - pointing north on the northern hemisphere of the earth and south on the southern hemisphere - the tower 320 and receiver 310 and, as in EP 2000669 A2 shown with one or more heliostaten aligned receivers 310 on the tower 320th

des Polarfeldes mit zunehmendem Abstand vom Receiver zu.Like the far field of a solar tower with surrounding heliostat field, the reflector surface density decreases

of the polar field with increasing distance from the receiver.

Polar tower solar tower systems typically have receiver heights of 50-150 m and heliostat fields with a diameter D _H of approximately five to six receiver heights, where 3 x H _R < D _H <7 x H _R.

For example, the "solar tower Jülich" described in [4] has a receiver height H _R of 55 m and a diameter D _{H of} the heliostat field of about 300 m.

For example, the "PS10 solar tower" described in [5] has a receiver height H _R = 115 m and a diameter D _H = 750 m, the "PS20 solar tower" has H _R = 165 m and D _H = 1000 m.

3. Solar tower system with heliostat field below the receiver (near field)

aufgestellt sind. Der Receiver 510 ist an ein Auslegersystem 520 hängend montiert, wie in Fig. 5 gezeigt. Für weitere Ausführungen siehe Seite 238 in [1] und US 4220140 . Aus Fig. 7.77 auf Seite 238 in [1] lässt sich ableiten, dass das Heliostatenfeld aus runden Heliostaten eine recht hohe Reflektorflächendichte

von ca. 60% hat, die mit rechteckigen Heliostaten nicht erreicht werden kann - siehe hierzu Seite 706 in [8]. Detailliertere veröffentlichte Daten der Reflektorflächendichte

des Solarturmsystems von Giovanni Francia sind nicht bekannt.In the 1960s, Giovanni Francia developed a first solar tower system in Italy, with the heliostat field below the receiver facing down and extending in the north, south, east and west directions. This is in Fig. 4 in which the heliostat field 430 and the position of the receiver 410 can be seen in plan view. In contrast to the far field explained above, the heliostat field is a near field in which the heliostat with constant reflector surface density

are set up. The Receiver 510 is suspended from a boom system 520, as in Fig. 5 shown. For further details see page 238 in [1] and US 4220140 , Out Fig. 7 .77 on page 238 in [1] it can be deduced that the heliostat field consisting of round heliostats has a fairly high reflector surface density

of about 60%, which can not be achieved with rectangular heliostats - see page 706 in [8]. More detailed published data of reflector surface density

of the solar tower system of Giovanni Francia are unknown.

The solar tower systems with heliostat data field developed by Giovanni Francia below the receiver typically have receiver heights H _R of less than 20 m and heliostat fields with a diameter D _H of less than two receiver heights H _R , ie D _H <2 x H _R , as shown in FIG Fig. 7 .77 on page 238 in [1]. More detailed published data is not known.

4. Solar tower system with north and south field

Another solar tower system described in [7], which was developed by the company eSolar Inc., homepage and seat address [6], is a mixture of a solar tower system with surrounding heliostat field and a solar tower system with polar field. As in the plan view in Fig. 6 It consists of a tower 620, on which there is a receiver 610 with two apertures, and a north field 631 and a south field 632, which together almost entirely surround the tower 620, like a surrounding heliostat field. In this case, the single receiver 610 has two apertures, one aligned with the north field and the other with the south field, as described in more detail in [7].

des gesamten Heliostatenfeldes. Siehe WO 2008/154521 A1 . Das Heliostatenfeld von eSolar Inc. unterscheidet sich jedoch von dem So-larturmsystem mit Nahfeld von Giovanni Francia darin, dass das Heliostatenfeld sich nicht unterhalb des Receivers befindet und die Reflektorflächendichte

kleiner als 50% ist.Characteristic of this heliostatic array of the solar tower system from eSolar Inc. is the uniform reflector surface density

of the entire heliostat field. Please refer WO 2008/154521 A1 , However, the heliostat data field of eSolar Inc. differs from Giovanni Francia's near-field solar-light system in that the heliostat field is not below the receiver and the reflector surface density

is less than 50%.

Solar tower systems with north and south field from eSolar Inc. typically have receiver heights H _R of approx. 50 m and heliostat fields with a diameter D _H of approx. Five receiver heights, ie D _H = 5 x H _R , as in [7] described.

Other known technologies for solar tower system are the most commonly used heliostats with fixed vertical axis suspension (FVA) and the known but mostly unused heliostats with fixed horizontal axis suspension (FHA), the hand of the FIGS. 7 to 10 be explained.

Heliostats with fixed horizontal axis suspension ( FHA )

In WO 02/070966 A1 . WO 2008/092194 A1 . WO 2008/092195 A1 and [8] Heliostats are described with fixed horizontal axis suspension (FHA). Heliostats with FHA differ from conventional heliostats, which have a fixed vertical axis suspension (FVA), by the volume of space in which the reflectors can move freely due to their suspension.

A heliostat has a first axis of rotation and a second axis of rotation arranged perpendicular to the first and is arranged on a mounting surface, wherein the first axis of rotation with respect to the mounting surface and the second axis of rotation with respect to the reflector are fixed.

In Fig. 7 are the known from [8] representations of the principle of a heliostat with FVA shown. In Fig. 7a is the principle of a heliostat shown with FVA and in Fig. 7b an exemplary rectangular heliostat and in Fig. 7c the corresponding volume of space in which the reflector of the heliostat can move freely due to the suspension. As in Fig. 7a and Fig. 7b In the case of a heliostat with FVA, the first axis of rotation 792 fixedly connected to the footprint or base is vertical or perpendicular to the footprint or base, while the second axis of rotation 793 is perpendicular to the first axis of rotation 792.

In Fig. 7c is the volume 799, in which the reflector can move freely due to the suspensions to recognize. The volume of the room is a barrel, which corresponds to a layer of a sphere in which the surfaces are located at the top and at the bottom, ie perpendicular to the first vertical axis of rotation 792 firmly connected to the surface Fig. 13 in WO 2008/092195 A1 and the accompanying explanations, a heliostat with FVA and associated volume of space in which the reflector of the heliostat can move freely due to the suspension, shown and explained.

In the known from [8] Fig. 8 It is shown at which intervals heliostats 890 can be set up with FVA, without the space volumes 899, in which the reflectors of the heliostats 890 can move freely, overlapping to avoid collision between the heliostats.

The well-known manufacturers of heliostats use heliostats with FVA.

In a heliostat with FHA, the first axis of rotation 992 fixedly connected to the footprint is parallel to the footprint or footprint, as in the systematic illustration in FIG Fig. 9a to see. The first fixed horizontal axis of rotation 992 is fixedly connected to the floor in the heliostat with FHA, as in WO 2008/092194 A1 and WO 2008/092195 A1 shown, while the second axis of rotation 993, can rotate about the first axis of rotation 992, perpendicular to the first.

As in Fig. 9b The space volume 999, in which the reflector of a heliostat with FHA can move freely, is the same as that of the heliostat with FVA, but rotated by 90 ° so that the axis of rotation 992, which is fixed in parallel with the mounting surface, is perpendicular to the surfaces of the barrel body. In Fig. 12 in WO 2008/092195 A1 and the accompanying explanations, a heliostat with FHA and associated volume of space in which the reflector of the heliostat can move freely due to the suspension is explained.

As in Fig. 10 and [8], heliostats with FHA can be placed in rows densely without the space volumes 1099, in which the reflectors of adjacent heliostat 1090 can move freely, overlapping. In Fig. 10 the theoretical maximum reflector surface density is shown for the given reflector size, with no safety margin between adjacent heliostats. In addition, the rows are offset from each other to make them as close as possible.

It can be seen that heliostats with FHA allow higher reflector surface densities than heliostats with FVA. As in Fig. 10 in [8] and derived from the corresponding explanations, the maximum possible reflector surface density of rectangular heliostats with FVA is approximately 58% in the ideal case, while rectangular heliostats with FHA allow significantly higher reflector surface densities, theoretically up to almost 100%. As is known from [8], the theoretically possible maximum reflector surface density ρ of a heliostat field increases when each reflector 995 is longer in the direction of the second axis of rotation 993 than in the direction perpendicular thereto.

In Fig. 6 in WO 02/070966 A1 and the accompanying explanations, the mechanical coupling of heliostats with FHA is shown.

In addition, various receiver technologies are known, in particular the in Fig. 11 shown cavity receiver.

receiver

There are receivers, as in Fig. 1 represented, in which the lateral surface is the absorber surface, as already explained. Other receivers have a target surface, ie aperture or absorber surface whose surface normals are directed essentially in the same direction.

In Fig. 11 is the cross section of a known from [9] cavity receiver to see. Concentrated solar radiation passes through the aperture 1111 in the cavity receiver and meets there on the absorber 1115, where the heat of a heat transfer medium is supplied. In the system shown, the heat transfer medium is air that enters the receiver through the inlet 1117 and leaves it through the outlet 1118, heated. This type of receiver also has a glass dome 1113 to hold the air in the receiver. The principle of a cavity receiver is also known from the patent US 4,220,140 respectively. WO 2008/153922 A1 known.

Task, solution and advantages of the invention

The object of the invention is to build a solar central receiver system in which the heliostat field can be used more efficiently.

This object is achieved by a solar central receiver system with a heliostat field according to claim 1 and a method for designing a claim 2

Thus, the one or more receivers can be held via a heliostat field, so that heliostats can also be installed directly below the receiver. In a downwardly oriented receiver, heliostats in the region below the receiver have particularly high efficiencies. By installing heliostats with rectangular reflectors, where the first axis of rotation is parallel to the footprint, Heliostats with fixed horizontal axis suspension (FHA), the heliostats with common footprint with very high Aufstelldichte in rows (preferably in east-west direction ) are installed.

von

> 60% zu installieren und diese Region optimal zu nutzen. Das Heliostatenfeld erstreckt sich somit kontinuierlich durchgehend in Nord-, Ost-, Süd- und West-Richtung, wie in Anspruch 14 aufgeführt. Mit zunehmendem Abstand von dieser Region nimmt der Wirkungsgrad ab. Mit zunehmender Anzahl an Heliostaten nimmt die Strahlungsleistung auf dem Receiver zu, jedoch nimmt die Leistungszunahme pro Heliostat mit jedem weiteren jeweils weniger effizienten Heliostaten ab. Durch die effiziente Nutzung der Region unterhalb des Receivers, die sich im Nahfeld des Heliostatenfeldes befindet, werden insgesamt weniger Heliostaten benötigt, als bei Solarturmkraftwerken mit umgebendem Heliostatenfeld, um die gleiche Strahlungsleistung auf dem Receiver zu erreichen.By using rectangular reflectors in which the reflector in the direction of the second axis of rotation is preferably longer than in the direction perpendicular thereto, the distances between the heliostat rows (preferably in the north-south direction) can be reduced the greater Ratio of side lengths is as in Fig. 10 in [8] and derived from the associated explanations. This makes it possible to have many heliostats in the region below the receiver, in which they have a particularly high efficiency, with a reflector surface density

from

> 60% to install and use this region optimally. The heliostat field thus extends continuously in the north, east, south and west directions, as recited in claim 14. With increasing distance from this region the efficiency decreases. As the number of heliostats increases, the radiated power on the receiver increases, but the power increase per heliostat decreases with each additional less efficient heliostat. Efficient use of the region below the receiver located in the near field of the heliostat field generally requires fewer heliostats than solar tower power plants with surrounding heliostat field to achieve the same radiant power on the receiver.

The installation of heliostats in rows (claim 2) allows the high Aufstelldichte in the near field (claim 3). Heliostats in east-west rows (claim 4) are the preferred design, wherein the alignment of the rows in north-south direction also makes sense and leads to almost the same efficiencies as heliostat series in east-west direction.

In applications where the footprint of the heliostat to the total base area is inclined by the angle α (claim 5), an alignment of the heliostat rows in north-south direction is a useful solution for heliostats with fixed quasi-polar axis suspension (FQA), through which also high reflector surface densities in the near field (claim 6) can be achieved. In addition, for the support systems of such heliostats comparable mounting system can be used, which were developed for the fixed installation of photovoltaic modules in solar parks. In addition, the possibility of mechanical coupling of the heliostat (claim 7) potential cost savings.

There are different support structures to hold the receiver above the heliostat field. In claim 8, a sheet system, called in claim 9 an explosive (triangular support structure), both of which have a supporting statics during the system in claim 10 has a suspended rope construction in which the bases, as well as the bow and blasting plant, are preferably installed outside the heliostat field so that the receiver hangs on a cable system above the heliostat field. The support structure in claim 11 is based on the concept of a tower crane in which a boom or cantilever holds the receiver above the heliostat field. This system is particularly suitable for small solar central receiver systems in which the receiver height H _{R is} less than about 70 m. Since in small systems, the length of the boom of a conventional tower crane is sufficient to have the foot beyond the heliostat field on the side facing away from the equator of the receiver, so the shading of the heliostat field can be reduced by the support structure of the receiver. In addition, the use of a tower crane allows the receiver in three dimensions to move (claim 12), such as a load that is moved by a tower crane, and so to increase the efficiency of the heliostat field by optimizing positioning of the receiver.

The receiver is mounted on the respective support structures such that it is attached to the local underside of the support structure, so that the support structure does not block the radiation reflected by the heliostat field (claim 13).

In the near range, a high unchanging reflector surface density is possible, but with increasing distance from the receiver, the heliostats must be installed with increasing distance to avoid that the heliostats block each other, ie that a heliostat can not reflect a part of the solar radiation on the receiver because another heliostat interferes with the beam path to the receiver and thus blocks it. Although the near field already transfers a large part of the radiation power to the receiver, nevertheless a far field is required (claim 15) in order to achieve higher radiation powers of over 100 MW _th on the receiver in a receiver height H _R of over 100 m to achieve. However, this far field can be much smaller due to the performance of the near field than in other solar tower systems with radiation powers of over 100 MW _th on receivers in a receiver height H _R of over 100 m, the far fields have as surrounding heliostat fields without near fields. As a result, these systems have heliostat fields with much larger diameters D _H of more than six receiver heights H _R. The peculiarity of the system according to the invention is the possibility to develop large solar Zentralreceiversysteme with receiver heights of over 100 m, the diameter D _{H are} smaller than six receiver heights, as stated in claim 17. This means that this invention not only leads to more efficient use of the heliostats but also to more efficient use of the footprint.

1. 1. Solarturmsystem mit umgebendem Heliostatenfeld
   1. a. Das erfindungsgemäße System hat ein Nahfeld, das sich unterhalb des Receivers erstreckt, in dem Heliostaten mit höchstem Wirkungsgrad installiert werden mit Reflektorflächendichte
      
      größer als 60% mit Heliostaten, die rechteckige Reflektorflächen und Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) oder fester Quasipolarachsen-Aufhängung (FQA) aufweisen.
   2. b. Das Heliostatenfeld ist durchgehend und nicht unterbrochen, wie das umgebende Heliostatenfeld, welches im Bereich um den Turm herum eine Aussparung hat, dort wo das erfindungsgemäße System Heliostaten mit dem höchsten Wirkungsgrad hat.
   3. c. Das erfindungsgemäße System hat einen Receiver mit nach unten gerichteter Apertur oder Absorber-Fläche welches nicht nur insofern vorteilhaft ist, dass so Heliostaten mit höchsten Wirkungsgrad im Nahfeld installiert werden können, sondern auch noch insofern, dass die Konvektions- und Strahlungsverluste bei einem nach unten zum Heliostatenfeld gerichteten Receiver minimiert sind.
   4. d. Der Receiver ist an eine Tragstruktur hängend montiert, die über das Heliostatenfeld reicht, was es ermöglicht, den Receiver auf eine Nahfeld unterhalbe des Receivers auszurichten, was zu höheren Wirkungsgraden der Heliostaten im Nahfeld führt.
   5. e. Das erfindungsgemäße System hat wesentlich kleinere Heliostatenfelder im Sinne kleinerer Reflektorfläche und kleinerer Grundfläche bei gleicher Strahlungsleistung auf der Zielfläche des Receivers zum Auslegungszeitpunkt.
2. 2. Solarturmsystem mit Nordfeld.
   1. a. Das erfindungsgemäße System hat ein Nahfeld, das sich unterhalb des Receivers erstreckt, mit Reflektorflächendichte e größer als 60% mit Heliostaten, die rechteckige Reflektorflächen und Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) oder fester Quasipolarachsen-Aufhängung (FQA) aufweisen.
   2. b. Das Heliostatenfeld erstreckt sich in alle Himmelsrichtungen vom Receiver aus.
   3. c. Das erfindungsgemäße System hat einen Receiver mit nach unten gerichteter Apertur oder Absorber-Fläche.
   4. d. Der Receiver ist an eine Tragstruktur hängend montiert, die über das Heliostatenfeld reicht.
3. 3. Solarturmsystem mit Heliostatenfeld unterhalb des Receivers
   1. a. Das erfindungsgemäße System hat zusätzlich zum Nahfeld auch ein Fernfeld mit abnehmender Reflektorflächendichte
      
      , wodurch große solare Zentralreceiversysteme mit Receiverhöhen H_R von über 100 m und Strahlungsleistungen von über 100 MW_th möglich sind. Bisherige Solarturmsysteme mit Heliostatenfeld unterhalb des Receivers haben Receiverhöhen H_R von weniger als 30 m und kein Fernfeld.
   2. b. Das erfindungsgemäße solare Zentralreceiversystem sieht für kleine Receiverhöhen H_R von weniger als 70 m ein Turmdrehkransystem als Tragstruktur für den Receiver vor, das außerhalb des Heliostatenfelds auf der vom Äquator abgewandten Seite des Receivers seinen Fußpunkt hat und dessen Receiverposition mit der Position der Sonne in bis zu drei Dimensionen verändert werden kann.
   3. c. Das erfindungsgemäße System hat ein Nahfeld mit Reflektorflächendichte
      
      größer als 60% mit Heliostaten, die rechteckige Reflektorflächen und Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) oder fester Quasipolarachsen-Aufhängung (FQA) aufweisen. In Fig. 17 ist die Draufsicht eines Nahfeldes mit Heliostaten mit FHA und 68% Reflektorflächendichte und in Fig. 22 ein Heliostatenfeld mit Heliostaten mit FQA und einem Nahfeld mit einer Reflektorflächendichte von ca. 71% dargestellt.
4. 4. Solarturmsystem mit Nord- und Südfeld,
   1. a. Das erfindungsgemäße System hat ein Nahfeld mit Reflektorflächendichte
      
      größer als 60% mit Heliostaten, die rechteckige Reflektorflächen und Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) oder fester Quasipolarachsen-Aufhängung (FQA) aufweisen.
   2. b. Das erfindungsgemäße System hat ein Fernfeld mit abnehmender Reflektorflächendichte
      
      .
   3. c. Das erfindungsgemäße System hat einen Receiver mit nach unten gerichteter Apertur oder Absorber als Zielfläche.
   4. d. Der Receiver ist an eine Tragstruktur hängend montiert, die über das Heliostatenfeld reicht.

The solar central receiver system according to the invention differs from previously known solar tower systems 1 to 4 in the following manner.

1. 1. Solar tower system with surrounding heliostat field
   1. a. The system according to the invention has a near field which extends below the receiver in which heliostats are installed with the highest efficiency with reflector surface density
      
      greater than 60% with heliostats having rectangular reflector surfaces and fixed horizontal axis suspension (FHA) or fixed quasi-polar axis suspension (FQA) heliostats.
   2. b. The heliostat field is continuous and unbroken, like the surrounding heliostat field which has a recess in the area around the tower where the system according to the invention has heliostats with the highest efficiency.
   3. c. The system according to the invention has a receiver with downwardly directed aperture or absorber surface which is not only advantageous in that heliostats can be installed with the highest efficiency in the near field, but also in that the convection and radiation losses at a down to Heliostatenfeld directed receiver are minimized.
   4. d. The receiver is suspended from a support structure that extends over the heliostat field, allowing the receiver to be aligned with a near field below the receiver, resulting in higher levels of heliostat efficiency in the near field.
   5. e. The system according to the invention has much smaller heliostat fields in the sense of smaller reflector area and smaller base area with the same radiant power on the target area of the receiver at the time of design.
2. 2. Solar Tower System with North Field.
   1. a. The inventive system has a near field extending below the receiver, with reflector surface density e greater than 60%, with heliostats having rectangular reflector surfaces and fixed horizontal axis suspension (FHA) or fixed quasi-polar axis suspension (FQA) heliostats.
   2. b. The heliostat field extends in all directions from the receiver.
   3. c. The system according to the invention has a receiver with downwardly directed aperture or absorber surface.
   4. d. The receiver is suspended from a supporting structure that extends over the heliostat field.
3. 3. Solar tower system with heliostat box underneath the receiver
   1. a. In addition to the near field, the system according to the invention also has a far field with decreasing reflector surface density
      
      , whereby large solar central receiver systems with receiver heights H _R of more than 100 m and radiation powers of over 100 MW _{th are} possible. Previous solar tower systems with heliostat field below the receiver have receiver heights H _R of less than 30 m and no far field.
   2. b. The solar central receiver system according to the invention provides for small receiver heights H _R of less than 70 m before a tower rotary crane system as support structure for the receiver, which has its base outside the heliostat field on the side facing away from the equator side of the receiver and its receiver position with the position of the sun in up to three dimensions can be changed.
   3. c. The system according to the invention has a near field with reflector surface density
      
      greater than 60% with heliostats having rectangular reflector surfaces and fixed horizontal axis suspension (FHA) or fixed quasi-polar axis suspension (FQA) heliostats. In Fig. 17 is the plan view of a near field with heliostats with FHA and 68% reflector surface density and in Fig. 22 a heliostat field with heliostat with FQA and a near field with a reflector surface density of about 71%.
4. 4. Solar tower system with north and south field,
   1. a. The system according to the invention has a near field with reflector surface density
      
      greater than 60% with heliostats having rectangular reflector surfaces and fixed horizontal axis suspension (FHA) or fixed quasi-polar axis suspension (FQA) heliostats.
   2. b. The system according to the invention has a far field with decreasing reflector surface density
      
      ,
   3. c. The system according to the invention has a receiver with downwardly directed aperture or absorber as target surface.
   4. d. The receiver is suspended from a supporting structure that extends over the heliostat field.

größer als 60% mit Heliostaten, die rechteckige Reflektorflächen und Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) oder fester Quasipolarachsen-Aufhängung (FQA) aufweisen.None of the four solar tower systems mentioned above has a near field with reflector surface density

greater than 60% with heliostats having rectangular reflector surfaces and fixed horizontal axis suspension (FHA) or fixed quasi-polar axis suspension (FQA) heliostats.

Brief description of the drawings

In the drawings, the same reference numerals are used in the figures for the same fact, and similar facts are shown when the last two final digits of the reference numerals are the same. The numbers in front of the two final digits indicate the number of the respective figure.

Fig. 1

eine perspektivische Ansicht eines bekannten Solarturmsystems mit einem Heliostatenfeld, welches sich aus einer Vielzahl von Heliostaten zusammensetzt, die die solare Strahlung auf einen Receiver konzentrieren, der sich auf einem Turm befindet (Stand der Technik gemäß US 4 172 443 ),

Fig. 2

eine Prinzipdarstellung einer Draufsicht auf ein bekanntes Solarturmsystem mit umgebendem Heliostatenfeld (Stand der Technik),

Fig. 3

eine Prinzipdarstellung einer Draufsicht auf ein bekanntes Solarturmsystem mit einem Polarfeld, in diesem Fall für ein System auf der nördlichen Hemisphäre mit dem Heliostatenfeld nördlich vom Receiver und Turm. (Stand der Technik),

Fig. 4

eine Prinzipdarstellung einer Draufsicht auf ein bekanntes Solarturmsystem von Giovanni Francia mit Heliostatenfeld unterhalb des Receivers (Stand der Technik),

Fig. 5

eine perspektivische Ansicht eines bekannten Solarturmsystems mit Heliostatenfeld unterhalb des Receivers, der an eine Auslegertragstruktur hängend montiert ist (Stand der Technik gemäß US 4 220 140 ),

Fig. 6

eine Draufsicht auf ein bekanntes Solarturmsystem mit Nord- und Südfeld (Stand der Technik aus [7] und WO 2008/154521 A1 ),

Fig. 7

a) und b), je eine Prinzipiendarstellung eines bekannten Heliostaten mit fester Vertikalachsen-Aufhängung (FVA) und c) eine perspektivische Ansicht des vom frei beweglichen Reflektors benötigten Raumvolumens (Stand der Technik aus [8] und WO 2008/092195 A1 ),

Fig. 8

eine Prinzipiendarstellung einer Draufsicht auf die Aufstellung von Heliostaten mit fester Vertikalachsen-Aufhängung (FVA) mit maximaler Reflektorflächendichte bei Vermeidung überlappender Raumvolumina (Stand der Technik gemäß [8]),

Fig. 9

a) eine Prinzipiendarstellung eines bekannten Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) und b) eine perspektivische Ansicht des vom frei beweglichen Reflektors benötigten Raumvolumens (Stand der Technik aus [8] und WO 2008/092195 A1 ),

Fig. 10

eine Prinzipiendarstellung einer Draufsicht auf die Aufstellung von Heliostaten mit fester Horizontalachsen-Aufhängung (FHA) mit maximaler Reflektorflächendichte bei Vermeidung überlappender Raumvolumina (Stand der Technik gemäß [8]),

Fig. 11

einen Querschnitt durch einen aus [9] bekannten Hohlraumreceiver bei dem die konzentrierte solare Strahlung durch die Apertur in den Hohlraumreceiver fällt und dort auf den Absorber trifft, an dem die Wärme einem Wärmeträgermediums zugeführt wird,

Fig. 12

eine perspektivische Ansicht einer erfindungsgemäßen Ausführungsform eines Modules von Heliostaten mit fester Quasipolarachsen-Aufhängung (FQA), bestehend aus fünf Gruppen von Heliostaten mit jeweils sechs Heliostaten einem gemeinsamen Tragsystem bestehend aus Tragrahmen und Beinen, wobei die erste Drehachse, die fest mit der Aufstellfläche verbunden ist, parallel zu der Aufstellfläche ist, die in der Abbildung durch den Tragrahmen aufgespannt wird und die um den Winkel α zur Gesamtgrundfläche des Heliostatenfeldes geneigt ist,

Fig. 13

eine Draufsicht auf eine erfindungsgemäße Ausführungsform einer Gruppe von Heliostaten bestehend aus sechs Heliostaten mit fester Quasipolarachsen-Aufhängung (FQA), wobei das Raumvolumen der Heliostaten eine dichte Positionierung der Heliostaten innerhalb der dargestellten Gruppe von Heliostaten erlaubt und die Nachführung der Heliostaten über die erste Drehachse direkt und die Nachführung über die zweiten Drehachsen 1393, die parallel sind, über eine gemeinsame Mechanik mechanisch gekoppelt sind,

Fig. 14

eine Übersicht über mögliche Trägstrukturen der erfindungsgemäßen Ausführungsformen des solaren Zentralreceiversystems mit jeweils hängend montiertem Receiver mit a) bogenförmiger Tragstruktur, b) einem Sprengwerk (dreieckförmige Tragstruktur), c) einer abgehängten Seilkonstruktion und d) ein Kransystem als Tragstruktur bestehend aus einer vertikalen Tragstruktur und einem Ausleger oder Kragarm, an dem der Receiver hängend montiert ist,

Fig. 15

a) einen Querschnitt durch eine erfindungsgemäße Ausführungsform eines Hohlraumreceiver und b) eine perspektivische Ansicht der Unterseite dieses Hohlraumreceivers, bei sich dem der Absorber in einem Hohlraum befindet, wobei die solare Strahlung durch die optische Öffnung, die Apertur, in den Hohlraum dringt und dort auf den Absorber fällt,

Fig. 16

eine Draufsicht auf eine erfindungsgemäße Ausführungsform eines solaren Zentralreceiversystems mit Aufteilung des Heliostatenfeldes aus Heliostaten mit FHA in Nah- und Fernfeld, wobei das Nahfeld sich unterhalb des Receivers bis zur rechteckigen Umrandung erstreckt und das Fernfeld sich vom Rand des Nahfeldes bis zur Umrandung des Heliostatenfeldes erstreckt,

Fig. 17

einen vergrößerten Ausschnitt der Draufsicht auf die erfindungsgemäße Ausführungsform von Fig. 16 zur Darstellung der Aufstellung der Heliostaten mit FHA im Nahfeld,

Fig. 18

einen vergrößerten Ausschnitt der Draufsicht auf die erfindungsgemäße Ausführungsform von Fig. 16 zur Darstellung der Aufstellung der Heliostaten mit FHA im Fernfeld, wobei die Abstände nicht maßstäblich sind und n die Nummerierung der Heliostatenreihen in West-Ost-Richtung und m die Nummerierung der Heliostatenreihen in Süd-Nord-Richtung ist.

Fig. 19

ein Diagramm für die Abstände der Heliostaten in Ost-West- und in Nord-Süd-Richtung in Abhängigkeit vom Abstand vom Receiver,

Fig. 20

a) einen Querschnitt durch eine erfindungsgemäße Ausführungsform eines Receivers mit externem Absorber und b) eine perspektivische Ansicht der Unterseite des Receivers mit externem Absorber, bei dem der Absorber eine Seite des Receivers darstellt,

Fig. 21

eine perspektivische Darstellung der erfindungsgemäßen Ausführungsform von vier Reihen von je vier Modulen von Heliostaten mit FQA, aufgestellt in parallelen Ost-West-Reihen,

Fig. 22

eine Draufsicht auf eine erfindungsgemäße Ausführungsform eines solaren Zentralreceiversystems mit Heliostaten mit FQA, wobei jeder Punkt einer Gruppe von Heliostaten wie in Fig. 13 gezeigt entspricht, mit Aufteilung des Heliostatenfeldes in Nah- und Fernfeld, wobei das Nahfeld sich unterhalb des Receivers bis zur rechteckigen Umrandung erstreckt und das Fernfeld sich vom Rand des Nahfeldes bis zur Umrandung des Heliostatenfeldes erstreckt,

Fig. 23

einen vergrößerten Ausschnitt der nicht maßstäblichen Draufsicht auf die erfindungsgemäße Ausführungsform von Fig. 22 zur Darstellung der Aufstellung der Heliostaten mit FQA im Nahfeld, wobei die Abstände A_Mod der Modulreihen in Nord-Süd-Richtung gleich sind im Nahfeld, so wie die Abstände A_OW der Heliostaten innerhalb der Modulreihen in Ost-West-Richtung,

Fig. 24

einen vergrößerten Ausschnitt der nicht maßstäblichen Draufsicht auf die erfindungsgemäße Ausführungsform von Fig. 22 zur Darstellung der Aufstellung der Heliostaten mit FQA im Fernfeld, wobei die Abstände A_Mod der Modulreihen in Nord-Süd-Richtung mit Abstand vom Receiver zunehmen, wie die Abstände der Heliostaten innerhalb der Modulreihen in Ost-West-Richtung, wobei innerhalb eines Modules die Abstände der Heliostaten Ost-West-Richtung gleich bleiben können und der Winkel α mit dem Abstand vom Receiver größer wird, wodurch die Modulreihen in der Draufsicht mit Abstand vom Receiver zunehmend schmaler erscheinen, so dass A_Mod (m) < A_Mod (m+1) und A_ModOW (n) < A_ModOW (n+1), wobei n die Nummerierung der Module in West-Ost-Richtung und m die Nummerierung der Modulreihen in Süd-Nord-Richtung ist,

Fig. 25

ein Diagramm für die Abstände der Heliostaten in Ost-West- und in Nord-Süd-Richtung in Abhängigkeit vom Abstand vom Receiver für ein Heliostatenfeld mit Heliostaten mit FQA und Darstellung des Winkels α der jeweiligen Module des Heliostatenfeldes in Abhängigkeit vom Abstand vom Receiver in Nord-Süd-Richtung, wobei positive Werte bedeuten, dass die Drehachse so gekippt ist, dass das höhere Ende Richtung Erdpol zeigt, während negative Werte bedeuten, dass das höhere Ende der Drehachse Richtung Äquator zeigt,

Fig. 26

einen Querschnitt einer erfindungsgemäßen Ausführungsform eines solaren Zentralreceiversystems mit Heliostatenfeld und Turmdrehkran als Tragstruktur dessen Darstellung aus [10] entnommen wurde, bestehend aus einer vertikalen Tragstruktur und einem Ausleger für den Receiver und einem Feld aus Heliostaten mit FHA, bestehend aus Nahfeld ohne Fernfeld, wobei die Position des Receivers drei Dimensionen verändert werden kann,

Fig. 27

eine Draufsicht auf eine erfindungsgemäße Ausführungsform eines solaren Zentralreceiversystems mit Heliostatenfeld, wobei jeder Punkt einem Heliostaten entspricht, und Turmdrehkran als Tragstruktur, bestehend aus vertikale Tragstruktur und Fußpunkt nördlich außerhalb des Heliostatenfeldes und einem Ausleger, um den Receiver über dem Heliostatenfeld zu halten, wobei der Ausleger kann durch eine vertikale Drehachse Achse in der vertikalen Tragstruktur gedreht und der Receiver entlang des Auslegers vor und zurück bewegt werden kann, wie exemplarische dargestellt, wobei die Position, in der sich der Receiver über dem Nullpunkt des Heliostatenfeldes befindet, die Situation ist, bei der die Sonne sich mittags genau südlich vom Heliostatenfeld befindet, während die andere Position die Situation darstellt, wenn sich die Sonne im Sommer morgens nord-östlich vom Heliostatenfeld befindet.

In the drawings show:

Fig. 1

a perspective view of a known solar tower system with a heliostat field, which is composed of a plurality of heliostats, which concentrate the solar radiation on a receiver, which is located on a tower (according to the prior art US 4,172,443 )

Fig. 2

a schematic representation of a plan view of a known solar tower system with surrounding heliostat field (prior art),

Fig. 3

a schematic representation of a plan view of a known solar tower system with a polar field, in this case for a system in the northern hemisphere with the heliostat field north of the receiver and tower. (State of the art),

Fig. 4

a schematic representation of a plan view of a known solar tower system by Giovanni Francia with heliostat field below the receiver (prior art),

Fig. 5

a perspective view of a known solar tower system with heliostat field below the receiver, which is mounted on a cantilever support structure hanging (prior art according to US 4,220,140 )

Fig. 6

a plan view of a known solar tower system with north and south field (prior art of [7] and WO 2008/154521 A1 )

Fig. 7

a) and b), each a principle representation of a known heliostat with fixed vertical axis suspension (FVA) and c) a perspective view of the space required by the freely movable reflector volume (prior art from [8] and WO 2008/092195 A1 )

Fig. 8

a schematic representation of a plan view of the installation of heliostats with fixed vertical axis suspension (FVA) with maximum reflector surface density while avoiding overlapping volumes (prior art according to [8]),

Fig. 9

a) a schematic representation of a known heliostat with fixed horizontal axis suspension (FHA) and b) a perspective view of the space required by the freely movable reflector volume (prior art of [8] and WO 2008/092195 A1 )

Fig. 10

a schematic representation of a plan view of the installation of heliostats with fixed horizontal axis suspension (FHA) with maximum reflector surface density at Avoiding overlapping room volumes (state of the art according to [8]),

Fig. 11

a cross-section through a known from [9] cavity receiver in which the concentrated solar radiation through the aperture in the cavity receiver falls and there meets the absorber, where the heat is supplied to a heat transfer medium,

Fig. 12

a perspective view of an embodiment of the invention of a module of heliostats with fixed quasi-polar axis suspension (FQA), consisting of five groups of heliostats, each with six heliostats a common support system consisting of support frame and legs, wherein the first axis of rotation, which is fixedly connected to the footprint , is parallel to the footprint, which is spanned in the figure by the support frame and which is inclined by the angle α to the total base area of the heliostat field,

Fig. 13

a plan view of an inventive embodiment of a group of heliostats consisting of six heliostats with fixed quasi-polar axis suspension (FQA), wherein the space volume of the heliostat allows a tight positioning of the heliostat within the illustrated group of heliostats and the tracking of the heliostat on the first axis of rotation directly and the tracking over the second axes of rotation 1393, which are parallel, are mechanically coupled via a common mechanism,

Fig. 14

an overview of possible support structures of the embodiments of the solar central receiver system according to the invention, each with suspended mounted receiver with a) arched support structure, b) an explosive device (triangular support structure), c) a suspended cable construction and d) a crane system as a support structure consisting of a vertical support structure and a jib or jib on which the receiver is suspended,

Fig. 15

a) a cross-section through an embodiment of a cavity receiver according to the invention and b) a perspective view of the underside of this cavity receiver, in which the absorber is located in a cavity, wherein the solar radiation penetrates through the optical aperture, the aperture, into the cavity and there the absorber falls,

Fig. 16

a plan view of an inventive embodiment of a solar central receiver system with division of the heliostat field from heliostat with FHA in near and far field, the near field extends below the receiver to the rectangular border and the far field extends from the edge of the near field to the border of the heliostat field

Fig. 17

an enlarged detail of the top view of the embodiment of the invention of Fig. 16 representing the formation of heliostats with FHA in the near field,

Fig. 18

an enlarged detail of the top view of the embodiment of the invention of Fig. 16 representing the formation of heliostats with FHA in the far field, where the distances are not to scale and n is the numbering of the heliostat series in west-east direction and m is the numbering of the heliostat series in south-north direction.

Fig. 19

a diagram for the distances of the heliostats in east-west and in north-south direction as a function of the distance from the receiver,

Fig. 20

a) a cross section through an inventive embodiment of a receiver with external absorber and b) a perspective view of the underside of the receiver with external absorber, in which the absorber is a side of the receiver,

Fig. 21

a perspective view of the embodiment according to the invention of four rows of four modules of heliostats with FQA, placed in parallel east-west rows,

Fig. 22

a plan view of an inventive embodiment of a solar central receiver system with heliostat with FQA, each point of a group of heliostats as in Fig. 13 shown, with the distribution of the heliostat field in near field and far field, wherein the near field extends below the receiver to the rectangular border and the far field extends from the edge of the near field to the border of the heliostat field,

Fig. 23

an enlarged section of the non-scale plan view of the embodiment of the invention of Fig. 22 for the representation of the heliostats with FQA in the near field, where the distances A _{mod of} the module rows in the north-south direction are equal in the near field, such as the distances A _{OW of} the heliostats within the module rows in east-west direction,

Fig. 24

an enlarged section of the non-scale plan view of the embodiment of the invention of Fig. 22 to represent the positioning of the heliostats with FQA in the far field, wherein the distances A _{mod of} the module rows in north-south direction with distance from the receiver increase, as the distances of the heliostats within the module rows in east-west direction, within a module the Distances of the heliostats east-west direction can remain the same and the angle α increases with the distance from the receiver, whereby the module rows in the Top view with distance from the receiver appear increasingly narrow, so that A _Mod ( m ) < A _Mod ( m + 1) and A _ModOW ( n ) <A _ModOW ( n + 1), where n is the numbering of modules in West-East Direction and m is the numbering of the module rows in south-north direction,

Fig. 25

a diagram for the distances of the heliostats in east-west and north-south direction as a function of distance from the receiver for a heliostat with heliostat with FQA and representation of the angle α of the respective modules of the heliostat field as a function of the distance from the receiver in North -South direction, where positive values mean that the rotation axis is tilted so that the higher end points towards the earth pole, while negative values mean that the higher end of the rotation axis points towards the equator,

Fig. 26

a cross section of an embodiment according to the invention of a solar central receiver system with heliostat field and tower crane as support structure whose representation was taken from [10], consisting of a vertical support structure and a boom for the receiver and a field of heliostats with FHA, consisting of near field without far field, the Position of the receiver three dimensions can be changed

Fig. 27

a plan view of an embodiment of a solar heliostat array according to the invention, each heliostat corresponding point, and tower crane as a support structure consisting of vertical support structure and base north of the heliostat field and a boom to hold the receiver above the heliostat field, the boom can be rotated by a vertical axis of rotation axis in the vertical support structure and the receiver along the boom The position in which the receiver is above the zero point of the heliostat field is the situation where the sun is at noon exactly south of the heliostat field, while the other position represents the situation when the sun is in the morning north-east of the heliostat field in the summer.

invention

von mehr als 60% und vorzugsweise mit einem Fernfeld, dessen Reflektorflächendichte

mit zunehmendem Abstand vom Receiver abnimmt, kombiniert. Die Erfindung umfasst auch solare Zentralreceiversysteme die ausschließlich aus einem Nahfeld mit gleichmäßiger Reflektorflächendichte

von mehr als 60%. Die hohe Reflektorflächendichte

im Nahfeld und Bereichen des Fernfeldes wird durch den Einsatz von Heliostaten mit rechteckigen Reflektoren und fester Horizontalachsen-Aufhängung (FHA) oder alternativ Heliostaten mit rechteckigen Reflektoren und fester Quasipolarachsen-Aufhängung (FQA) erreicht. Heliostaten mit fester Horizontalachsen-Aufhängung sind in WO 02/070966 A1 , WO 2008/092194 A1 , WO 2008/092195 A1 und [8] beschrieben. Heliostaten mit fester Quasipolarachsen-Aufhängung (FQA) werden in dieser Erfindung zum ersten Mal beschrieben. Das Heliostatenfeld konzentriert die solare Strahlung auf einen Receiver, dessen Zielfläche, die Apertur, der thermische Absorber oder der photovoltaische Absorber, einen Normalenvektor hat der nach unten auf das Heliostatenfeld gerichtet ist, das sich unterhalb des Receivers in Nord-, Ost-, Süd- und West-Richtung erstreckt. Der Receiver ist an eine Tragstruktur hängend montiert, die sich über das Heliostatenfeld erstreckt. Diese Tragstruktur kann zum Beispiel ein Bogen (siehe Fig. 14a), ein Sprengwerk (siehe Fig. 14b) oder eine abgehängte Seilkonstruktion (siehe Fig. 14c) mit mehreren Fußpunkten oder ein Kransystem mit Ausleger oder Kragarm und einem Fußpunkt (siehe Fig. 14d) sein. Idealerweise liegen die Fußpunkte außerhalb des Heliostatenfeldes, können aber auch innerhalb des Feldes sein, zum Beispiel aus statischen Gründen.The aim of the invention is to build solar central receiver power plants, in which the heliostat data fields can be used more efficiently. For this purpose, a heliostat field consisting of a near field with uniform reflector surface density

greater than 60% and preferably with a far field whose reflector surface density

decreases with increasing distance from the receiver, combined. The invention also encompasses solar central receiver systems which consist exclusively of a near field with a uniform reflector surface density

of more than 60%. The high reflector surface density

in the near field and in the far field is achieved by using heliostats with rectangular reflectors and fixed horizontal axis suspension (FHA) or alternatively heliostats with rectangular reflectors and fixed quasi-polar axis suspension (FQA). Heliostats with fixed horizontal axis suspension are in WO 02/070966 A1 . WO 2008/092194 A1 . WO 2008/092195 A1 and [8]. Solid quasi-polar axis suspension (FQA) heliostats are described for the first time in this invention. The heliostat field focuses the solar radiation onto a receiver whose target surface, the aperture, the thermal absorber or the photovoltaic absorber, has a normal vector directed downwards onto the heliostat field located below the receiver in north, east, south and south. and west direction. The receiver is mounted suspended from a support structure that extends over the heliostat field extends. This support structure may, for example, a bow (see Fig. 14a ), a blasting plant (see Fig. 14b ) or a suspended rope construction (see Fig. 14c ) with several feet or a crane system with boom or cantilever and a foot point (see Fig. 14d ) be. Ideally, the foot points are outside the heliostat field, but can also be inside the field, for example for static reasons.

The invention enables solar central receiver systems with receiver heights H _R of over 100 m with radiated power on the target surface of the receiver of over 100 MW _th at design time (typically on the day of the summer solstice at 12 noon, solar time) and a size of the heliostat field whose diameter D _H smaller than six receiver heights H _R. This means that this invention not only leads to more efficient use of heliostats, but also to more efficient use of the footprint.

Heliostats with Fixed Quasipolar Axle Suspension (FQA)

An alternative heliostat according to the invention for heliostat data fields with high reflector surface density is the fixed quasi-polar axis suspension (FQA) heliostat. The heliostat with FQA is a further development of the heliostat with FHA.

In Fig. 12 For example, a fixed quasi-pole axis suspension (FQA) helicopter-mounted module 1280 is shown in which the first pivot 1292 is fixedly connected to the frame 1285 of the module such that this first pivot 1292 faces the total base on which the legs 1287 of the module 1280 walk to one in Fig. 12 drawn angle α is inclined. The second axes of rotation 1293 are perpendicular to the first and move with the reflectors 1295, with which they are firmly connected to the first axis of rotation 1292. A heliostat with FQA is thus a further development of a heliostat with FHA, in which the footprint to which the first axis of rotation 1292 connected in parallel is inclined at an angle α to the total base area. The inclined footprint is equal to the area in Fig. 12 is clamped by the frame 1285 of the modular system.

In the in Fig. 12 illustrated preferred embodiment, the footprint spanned by the module frame 1285 is tilted about the east-west axis relative to the total base area and the first axis of rotation 1292 aligned in north-south direction. Due to the movement around the first axis of rotation 1292, the heliostats mainly follow the daily course of the sun in an east-west direction, while the heliostats follow the movement of the second axis of rotation 1293 mainly the height of the sun.

In the execution in Fig. 12 Each six heliostats with FQA and a common set-up area each form a group of heliostats 1283. Five such groups of heliostats form a module with a common support system.

Fig. 13 shows the top view of a group of heliostat 1383 from six heliostats 1390 with FQA. The volume 1399 of the heliostat 1390 allows a dense positioning of the heliostat within the illustrated group of heliostats. The tracking of the reflectors of the heliostats may be coupled via the first axis of rotation 1392. Likewise, the movement about the second axes of rotation 1393, which are parallel, can be coupled via a common mechanism 1394.

In the in Fig. 12 and Fig. 13 In the preferred embodiment shown, groups of heliostats 1283 and 1383 with common footprint are installed in rows so as to have a common first axis of rotation 1292 and 1392 such that the movement about this first axis of rotation 1292 and 1392 is mechanically coupled. The spatial volumes 1299 and 1399 of the reflectors 1295 and 1395 defined by the orientation of the axes of rotation allow, as in the heliostats with FHA, the high mounting density in rows.

The orientation of the common footprint by the angle α and thus the first axis of rotation parallel thereto is oriented at the axis of the earth around which the earth moves. In a preferred embodiment, the first axis of rotation of a FQA heliostat having a position on the side of the receiver remote from the equator would be substantially parallel to the earth axis, ie, the angle α would be substantially the same as the latitude at the location. In other positions, north or south of it, the angle α is larger or smaller. With increasing distance from the receiver to the next Erdpol hin the first axis of rotation would be increasingly tilted into the vertical, that is, the angle α would be larger, while heliostats with positions closer to the equator would be increasingly tilted into the horizontal, that is, the angle α would be smaller. On the equator side facing the receiver there may be regions in which the footprint and the first axis of rotation may be tilted in the other direction.

The angle α of the common set-up of a group of heliostats and their first axis of rotation is chosen so that the adjacent heliostats within the group of heliostats have a high mounting density, without mutually shadowing and blocking. For this purpose, the angle α is chosen so that the heliostats at the equinox in March and September at 12 noon solar time in operation are essentially in one plane. Modules with groups of heliostats with FQA are installed with such north-south distances that mutual shading and blocking of the heliostats is low. Blocking means that a heliostat can not reflect part of the solar radiation onto the receiver, because another heliostat interferes with the beam path to the receiver and thus blocks it, while shadowing means that one heliostat is blocking another heliostat.

The movement of the heliostats about the second axis of rotation 1293 and 1393 may also be mechanically coupled, but need not. In Fig. 13 For example, the substantially linear motion of the mechanism 1394 allows for common movement of the heliostat 1390 about its second axis of rotation 1393.

The mechanical coupling of heliostats with FHA in similar form is in Fig. 6 in WO 02/070966 A1 and the explanatory notes in a similar form.

In the in Fig. 12 illustrated preferred embodiment, the reflectors 1295 have an elongated shape, so that the length L _{Hel is} at least twice as large as the width B _HEL . In the design in Fig. 12 For example, the 1295 reflector is at least six times longer than it is wide ( L _Hel > 6 x B _HEL ).

The reflectors of the heliostats may be flat or concentrically curved along the length.

As in Fig. 12 The space volumes resulting from the oblong shape of the reflectors allow a high setup density of adjacent rows of heliostats within a common module 1280. The high setup density of elongated rectangular reflectors of heliostats with FHA is in Fig. 10 in [8]. For heliostats with FQA, the same relationships apply.

embodiments Embodiment 1

An exemplary design for a solar central receiver system based on this patent has been designed with the following characteristics:

Assumptions for the design of the solar central receiver system

Design time: June 21, 12 noon, solar time.

Location: latitude 34 ° N, north latitude, (e.g., North Africa or Southern California, USA).

Assumption: direct normal radiation (solar radiation power) at design time: 1000 W / m ² .

Radiation power (thermal power in megawatts - MW _th ) on the target surface of the receiver at the design point: 140 MW _th .

receiver

The receiver used is a cavity receiver, as in Fig. 15 shown in which the absorber 1515 is located in a cavity 1512. The solar radiation penetrates through the optical opening, the aperture 1511, into the cavity 1512 and there it falls onto the absorber 1515, which converts the solar radiation into heat. The absorber 1515 may also have various shapes and structures. The normal vector n _{R of} the aperture area points downward. B _{R_NS} is the width of the rectangular aperture 1511 in north-south direction and B _{R_OW} in east-west direction. For the dimensions of the aperture 1511 of the cavity receiver, as in Fig. 15 shown: $$B_{\mathit{R\_NS}}=12.5m.B_{\mathit{R\_OW}}=12.5m\left(156.25{\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="imgf0011.png,imgf0018.png"\; state="\{\{state\}\}">m</figure-callout>}}^2\right)$$

The height of the receiver above the heliostat field of the receiver height is H _R = 150 m.

Receiver support structure

The receiver is mounted hanging on a support structure that holds the receiver freely over the heliostat field. This can be for example a bow system with two feet, as in Fig. 14a shown. The arc would stretch from east to west across the heliostat field.

heliostats

Heliostats with fixed horizontal axis suspension (FHA).

Reflector area F _Hel = L _Hel x B _Hel = 7.2225 m ² .

L _Hel = 3.21 m (length), B _Hel = 2.25 m (width).

The reflectors of the heliostats are flat and not concentrically curved.

Heliostat field

The heliostats are placed in parallel rows in east-west direction, with the heliostats are also in north-south direction in rows. Please refer Fig. 17 and Fig. 18 , In other interpretations, the heliostats of adjacent east-west series can also be separated by a half heliostat spacing A _OW (cf. Fig. 17 ) are offset from each other, as in Fig. 10 ,

The heliostat field consists of a near field 1636 and a far field 1638.

In Fig. 16 is the described heliostat field, consisting of a near field 1636 and the far field 1638, shown in a plan view, each individual point represents the position of a single heliostat in north-south direction and east-west direction. The origin of the coordinate system is defined by the position of the center of the receiver 1610, here represented by a larger non-scale point. The outer border of the near field 1637 is at the same time the border to the far field. The outer border of the far field is at the same time the outer border of the entire heliostat field 1639.

aufgestellt, wie aus dem vergrößerten Ausschnitt der Draufsicht auf das Nahfeld in Fig. 17 ersichtlich. Die Reflektorflächendichte

im Nahfeld ist gleich der maximalen Reflektorflächendichte

im Heliostatenfeld.In the near field 1636 the heliostats are at constant distances to each other with the maximum reflector surface density

set up, as shown in the enlarged section of the plan view of the near field in Fig. 17 seen. The reflector surface density

in the near field is equal to the maximum reflector surface density

in the heliostat field.

The near zone of the heliostat field extends according to Fig. 16 in east-west direction from 85 m east of the receiver to 85 m west of the receiver and in north-south direction from 115 m north of the receiver to 150 m south of the receiver.

In Fig. 17 is a detail from the top view of a near field to scale shown with the distances of the heliostat 1790 in east-west and north-south directions.

In the east-west direction, the heliostats are placed in the near field at distances A _OW of 2.65 m, ie there is a gap Z _OW of 0.4 m between the reflectors with width B _Hel of 2.25 m, when these are in horizontal parking position in which the reflectors are horizontal and the long side of the heliostats oriented in north-south direction, as in the plan view in Fig. 17 shown.

The high deployment density within the East-West series of approximately 85% (= 2.25 m / 2.65 m) is possible through the use of heliostats with fixed horizontal axis suspension (FHA), as in WO 02/070966 A1 . WO 2008/092194 A1 and WO 2008/092195 A1 described. The fixed horizontal axis suspension of the heliostats even allows a fundamentally higher deployment density within the East-West series, if the installation and production is precise and local safety standards are met. In Fig. 10 shows how heliostats 1090 with FHA can be set up with maximum setup density in east-west direction without tolerances between the heliostats.

In the north-south direction, the heliostat series are set up in the near field at intervals A _NS of 4.01 m, ie there is one each between the reflectors with the length L _Hel = 3.21 m (and thus 3.21 m wide rows) Gap Z _NS , of 0.8 m there, if this are in horizontal parking position. Please refer Fig. 17 The setup density of the rows can in principle also be higher if the heliostat rows are each separated by a half heliostat spacing A _OW (cf. Fig. 17 ) are offset as in Fig. 10 shown.

68%The combination of the setup density in east-west and north-south results in a constant reflector surface density of near field ${\mathrm{\rho }}_{\mathrm{Max}}=\mathrm{ca}\mathrm{,}$

68%

im Nahfeld entspricht der maximalen Reflektorflächendichte

, die im Nahfeld wie in Fig. 17 nach folgender Formel berechnet wird: $${\varrho }_{\max }=\varrho =\left(B_{\mathit{HEL}}\times L_{\mathit{HEL}}\right)/\left(A_{\mathit{OW}}\times A_{\mathit{NS}}\right)\mathrm{.}$$

The constant reflector surface density

in the near field corresponds to the maximum reflector surface density

that in the near field as in Fig. 17 calculated according to the following formula: $${\rho }_{\mathrm{Max}}=\rho =\left(B_{\mathit{HEL}}\times L_{\mathit{HEL}}\right)/\left(A_{\mathit{OW}}\times A_{\mathit{NS}}\right)\mathrm{,}$$

58% erreicht werden, wie in [8] erläutert und hergeleitet.With rectangular heliostats with fixed vertical axis suspension (as all known commercial heliostats have), in the ideal case (square mirrors) a theoretically maximum reflector surface density of ${\mathrm{\rho }}_{\mathrm{Max}}=\mathrm{ca}\mathrm{,}$

58%, as explained and derived in [8].

In the far field, the distances increase with increasing distance from the receiver 1610 in both east-west and north-south orientation. In the far field, the distances A _OW in east-west direction grow from 2.65 m up to 5 m and the distances A _NS in north-south direction from 4.01 m up to 8 m.

In Fig. 18 an enlarged section of the top view of a far field is shown. The representation of the distances shows only the principle. The distances are not to scale. It can be seen that in the illustrated case, in which the receiver 1610 is located southwest of this field, the distances increase from west to east and south to north.

The increase in the distances of the heliostats in east-west and north-south direction is in Fig. 19 shown.

The entire heliostat field extends in north-south direction from 340 m north of the receiver 1610 to 285 m south of the receiver 1610 and in east-west direction from 330 m east of the receiver to 330 m west of the receiver 1610.

beträgt ${\mathrm{\varrho }}_{\mathrm{Gesamt}}=\mathrm{52}\%$

The reflector surface density for the entire heliostat field

is ${\mathrm{\rho }}_{\mathrm{total}}=\mathrm{52}\%$

The scope of the heliostat field is described in Fig. 16 a shape that runs outside of a circle and at the same time within a square. The center of the heliostat field is about 25 m north of the receiver 1610, as from the in Fig. 16 drawn scale information is visible. The receiver 1610 is shifted about 25 m from the center of the field to the south. The diameter of the heliostat field is approx. 700 m and thus approx. 4.5 x H _R.

The heliostat field is continuously continuous and only then interrupted for the base points of the support structure, should the technical implementation of the span of the support structure make footprints within the heliostat field necessary.

Summary of the essential features of embodiment 1

• Receiver height H _R : 150 m above heliostat field.
• Surface of the receiver aperture: 12.5m x 12.5m = 156.25 m ² .
• Receiver orientation: Normal vector of the aperture area of the receiver 1610 directed vertically downwards as in Fig. 15 shown.
• Support structure: bow system, as in Fig. 14a , East-West over Heliostatenfeld, consisting of near field 1636 and far field 1638, tense.
• Heliostat field with constant reflector surface density
  
  in the near field 1636, which is equal to the maximum reflector surface density
  
  of about 68%.
  1. 1. Heliostats with fixed horizontal axis suspension for high deployment density within a row in east-west direction or alternatively within a row in north-south direction.
  2. 2. Heliostat data field has reflector area density at close range $\mathrm{\rho }={\mathrm{\rho }}_{\mathrm{Max}}=\mathrm{68}\%>\mathrm{60}\%\mathrm{,}$
     
  3. 3. Heliostats field that extends around the receiver in north, east, south, and west directions, representing a continuous (uninterrupted) area.
• In the far field increasing distances between the heliostats in east-west and north-south direction.
• Reflector surface density for the entire heliostat field
  
  is ${\mathrm{\rho }}_{\mathrm{total}}=\mathrm{52}\%\mathrm{,}$
  
• Heliostats with fixed horizontal axis suspension for high installation density in east-west direction.
• Dimensions of the near field 1636: 85 meters east to 85 meters west of the receiver and 115 meters north of the receiver and 150 meters south of the receiver 1610.

Embodiment 2

Another exemplary design for a solar central receiver system based on this patent using the type of fixed quasi-polar axis suspension (FQA) heliostat of the present invention has been designed with the following characteristics:

Assumptions for the design of the solar central receiver system

• Design time: June 21, 12 noon, solar time.
• Location: latitude 34 ° N, north latitude, (e.g., North Africa or Southern California, USA).
• Assumption: direct normal radiation (solar radiation power) at design time: 1000 W / m ² .

receiver

The receiver used is a receiver with external absorber, as in Fig. 20 shown at the one absorber 2015 on one side of the receiver. The surface of the absorber 2015 is therefore also the same as the optical opening of the receiver, the aperture 2011. In other cases, the absorber 2015 may also have a non-flat surface. The normal vector n _{R of} the absorber surface points downward. B _{R_NS} is the width of the rectangular absorber 2015 in north-south direction and B _{R_OW} in east-west direction. For the dimensions of the Absorber 2015 applies as in Fig. 20 shown: $$B_{\mathit{R\_NS}}=12.5m.B_{\mathit{R\_OW}}=12.5m\left(156.25{\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="imgf0011.png,imgf0018.png"\; state="\{\{state\}\}">m</figure-callout>}}^2\right)\mathrm{,}$$

The height of the receiver above the heliostat field of the receiver height is H _R = 150 m.

Receiver support structure

The receiver is mounted hanging on a support structure that holds the receiver freely over the heliostat field. This can be for example a bow system with two feet, as in Fig. 14a shown. The arc would stretch from east to west across the heliostat field.

heliostats

L_Hel = 3,21 m (Länge), B_Hel = 0,425 m (Breite). Siehe Fig. 13.The FQA heliostats 1290 are assembled into groups of 6 heliostats each, with five sets of heliostat 1283 assembled into a module 1280 having a common support system consisting of a support frame 1285 and legs 1287, as in FIG Fig. 12 shown. $$\mathrm{reflector\; surface}{\mathit{F}}_{\mathit{Hel}}={\mathit{L}}_{\mathit{Hel}}\mathit{x}{\mathit{B}}_{\mathit{Hel}}=1.36425{\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="imgf0011.png,imgf0018.png"\; state="\{\{state\}\}">m</figure-callout>}}^2\mathrm{,}$$

L _Hel = 3.21 m (length), B _Hel = 0.425 m (width). Please refer Fig. 13 ,

The gaps Z _NS between the six heliostats 1390 within a group of heliostats 1383 are 0.05 m, similar to FIG Fig. 13 shown. The distances A _OW between the five groups of heliostats 1283 are equal within one module 1280. However, the distances A _OW between the groups of heliostats 1283 may differ from one module 1280 to another.

The heliostats are curved along the length with a focal length of 300 m and concentrating.

Heliostat field

The heliostat field consists of a plurality of heliostat-type modules 1280 with FQA coupled coupled around the first and second axes of rotation within the groups of heliostats 1283.

The heliostats with FQA are placed in parallel rows of 2180 modules of heliostat with FQA in east-west direction, as in Fig. 21 shown in a perspective view for four rows of four modules. In the in Fig. 21 The distances A _{OW of} the groups of heliostats 2183 within the modules 2180 are constant, as are the distances between the rows of modules 2180 as well as the angle α . This is characteristic of a section of the near field. The distances, angles and sizes are only to scale.

The heliostat field consists of a near field 2236 and a far field 2238.

In Fig. 22 the described heliostat field, consisting of a near field 2236 and the far field 2238, is shown in a plan view, with each individual point representing the position group of heliostat 1383, as in FIG Fig. 13 shown, represented. The origin of the coordinate system is defined by the position of the center of the receiver 2210, here represented by a larger non-scale point. The outer border of the near field 2237 is at the same time the border to the far field. The outer border of the far field is at the same time the outer border of the entire heliostat 2239.

aufgestellt, wie aus dem vergrößerten Ausschnitt der Draufsicht auf das Nahfeld in Fig. 23 besser ersichtlich. Die Reflektorflächendichte

im Nahfeld ist gleich der maximalen Reflektorflächendichte

im Heliostatenfeld.In the near field 2236, the distances A _{OW of} the groups of heliostats in east-west direction are constant and with the maximum reflector surface density

set up, as shown in the enlarged section of the plan view of the near field in Fig. 23 better visible. The reflector surface density

in the near field is equal to the maximum reflector surface density

in the heliostat field.

The near zone of the heliostat field extends according to Fig. 22 in east-west direction from 80 m in the east of the receiver to 80 m west of the receiver and in north-south direction from 83 m north of the receiver to 173 m south of the receiver.

In Fig. 23 is a section of the top view of a near field not shown to scale. The distances A _{Mod of} the module rows in north-south direction are equal in the near field, as are the distances A _{OW of} the heliostats within the module rows in east-west direction.

In the East-West direction, the heliostats are placed in the near field with intervals A _OW of 3.61 m, which means that there is between the reflectors with length L _Hel of 3.21 m in each case an intermediate space Z _OW of 0.4 m, if the reflectors are aligned in parallel as shown.

89% (= 3.21 m / 3.61 m) is possible due to the use of heliostats with FQA and space volumes of the heliostats required for the free movement due to reflectors. have in the east-west direction substantially greater length L _Hel than width B _HEL ( L _Hel > 6 x B _HEL ), as in Fig. 12 shown. The use of heliostats with FQA even allows a fundamentally higher deployment density within the East-West ranks when installing and manufacturing is accurate and local safety standards are met.

In the north-south direction, the module rows in the near field with distances A _Mod of 3.20 m are set up, ie that from B _hel = 0.425 m for each six heliostats per group of heliostats an erection density in north-south direction of 80% (= 6 x 0.425 m / 3.20 m). In principle, the installation density of the rows can also be higher if the installation and production are precise and local safety standards are met.

71%.The combination of the setup density in east-west and north-south results in a constant reflector surface density of near field ${\mathrm{\rho }}_{\mathrm{Max}}=\mathrm{ca}\mathrm{,}$

71%.

In the far field, the distances increase with increasing distance from the receiver 2210 in both east-west and north-south orientation. The distances of the heliostats grow in the far field in east-west direction from 3.61 m up to 6.39 m and the distances of the module rows in north-south direction from 3.20 m up to 6.63 m.

In Fig. 24 is a section of the top view of a far field with heliostat with FQA shown. The representation of the distances shows only the principle. The distances are not to scale. It can be seen that in the illustrated case, where the receiver 2210 is located southwest of this field patch, the distances increase from west to east and south to north.

The angle α of the footprint and the first axis of rotation with respect to the total base area is maximum at the module rows at the northern end of the heliostat field and decreases towards the south, as well as in Fig. 25 shown. It can be seen that the angle α changes in 5 ° steps. This happens from production engineering Considerations, theoretically, the angle α could change continuously. It can also be seen that the angle α can also be negative to the south of the receiver, where positive values mean that the axis of rotation is tilted so that the higher end points towards the earth pole (north), while negative values mean that the higher end of the axis of rotation Towards the equator (south).

The entire heliostat field extends in north-south direction from 340 m north of the receiver 2210 to 285 m south of the receiver 2210 and in east-west direction from 330 m east of the receiver to 330 m west of the receiver 2210.

beträgt ${\mathrm{\varrho }}_{\mathrm{Gesamt}}=\mathrm{51}\%\mathrm{.}$

The reflector surface density for the entire heliostat field

is ${\mathrm{\rho }}_{\mathrm{total}}=\mathrm{51}\%\mathrm{,}$

The scope of the heliostat field is described in Fig. 22 a shape that runs outside of a circle and at the same time within a square. The center of the heliostat field is about 25 m north of the receiver 2210, as from the in Fig. 22 drawn scale information is visible. The receiver 2210 is shifted about 25 m from the center of the field to the south. The diameter of the heliostat field is approx. 700 m and thus approx. 4.5 x H _R.

The heliostat field is continuously continuous and only then interrupted for the base points of the support structure, should the technical implementation of the span of the support structure make footprints within the heliostat field necessary.

Summary of the essential features of exemplary embodiment 2

• Receiver height H _R : 150 m above heliostat field.
• Area of the absorber of the receiver: 12.5m x 12.5m = 156.25 m ² .
• Receiver orientation: Normal vector of the absorber surface of the receiver 2210 directed vertically downwards, as in Fig. 20 shown.
• Support structure: bow system, as in Fig. 14a , East-West over Heliostatenfeld consisting of near field 2236 and 2238 farfield stretched.
• Heliostat field with constant reflector surface density
  
  in the near field 2236 equal to the maximum reflector surface density
  
  of about 71%.
  1. 1. Heliostats with fixed quasi-polar axis suspension for high reflector surface density.
  2. 2. Heliostat field at close range Reflector surface density $\mathrm{\rho }={\mathrm{\rho }}_{\mathrm{Max}}=71\%>\mathrm{60}\%\mathrm{,}$
     
  3. 3. Heliostat field extending around the receiver in the north, east, south and west directions, representing a continuous (uninterrupted) area.
• In the far field increasing distances between the rows of modules of the heliostats in north-south direction and the heliostats in east-west direction.
• Reflector surface density for the entire heliostat field
  
  is ${\mathrm{\rho }}_{\mathrm{total}}=\mathrm{51}\%\mathrm{,}$
  
• Heliostats with fixed quasi-polar axis suspension for high reflector surface density.
• Dimensions of the near field 2236: 83 m east to 83 m west of the receiver and 80 m north of the receiver and 173 m south of the receiver 2210th
• In the far field 2238 increasing distances between the heliostats in east-west and between the module rows in north-south direction.

Embodiment 3

Another exemplary design for a small solar central receiver system based on this patent using heliostats with fixed horizontal axis suspension in a heliostat field, which consists exclusively of a near field and in which the support structure is a tower crane with boom, which allows the movement of the receiver in up to three dimensions:

Assumptions for the design of the solar central receiver system

Design time: June 21, 12 noon, solar time.

Location: latitude 34 ° N, north latitude, (e.g., North Africa or Southern California, USA).

Assumption: direct normal radiation (solar radiation power) at design time: 1000 W / m ² .

Radiation power (thermal power in megawatts - MW _th ) on the target surface of the receiver at the design point: 2 MW _th .

receiver

The receiver used is a cavity receiver, as in Fig. 15 shown. The normal vector n _{R of} the aperture area points downward. B _{R_NS} is the width of the rectangular aperture 1511 in north-south direction and B _{R_OW} in east-west direction. For the dimensions of the aperture 1511 of the cavity receiver, as in Fig. 15 shown: $$B_{\mathit{R\_NS}}=3m.B_{\mathit{R\_OW}}=6m\left(18{\mathrm{<figure-callout\; id="2"\; label="m"\; filenames="imgf0011.png,imgf0018.png"\; state="\{\{state\}\}">m</figure-callout>}}^2\right)$$

The height of the receiver above the heliostat field of the receiver height is H _R = 45 m.

Receiver height via heliostat field: H _R = 45 m.

Receiver support structure

The support structure is, as in Fig. 26 shown, a tower crane consisting of a vertical support structure 2621 and a boom 2622 to which a receiver 2610 hanging above the heliostat data field is mounted. The base 2623 of the vertical support structure 2621 of the tower crane is north of the heliostat field.

As in Fig. 27 can be seen, the boom 2722 can be rotated about a vertical axis of rotation in the vertical support structure 2721. In addition, the receiver 2710 can be moved back and forth along the boom 2722. As a result, the position of the receiver 2710 can be changed depending on the position of the sun and thus the efficiency of the heliostat field can be optimized. It can be seen that the receiver 2710 is also in different positions along the boom 2722 in the two illustrated boom positions. The position in which the receiver 2710 is above the zero point of the heliostat field is the situation where the sun is just south of the heliostat field at noon, while the other position represents the situation when the sun is shining north-east in the summer Heliostat box is located.

In principle, it is also possible that the position of the receiver 2710 in the height H _R can be changed.

heliostats

Heliostats with fixed horizontal axis suspension (FHA)
Reflector area F _Hel = L _Hel x B _Hel = 7.2225 m ²
L _Hel = 3.21 m (length), B _Hel = 2.25 m (width)

The reflectors of the heliostats are curved and concentric along the length with a focal length of 49.5 m.

Heliostat field

The heliostats are placed in parallel rows in east-west direction, with the heliostats are also in north-south direction in rows. Please refer Fig. 27 , In other interpretations, the heliostats of adjacent east-west series can also be separated by a half heliostat spacing A _OW (cf. Fig. 17 ) are offset from each other, as in Fig. 10 ,

The heliostat field consists of near field and no far field.

In Fig. 27 is the described heliostat data field, consisting of a near field and no far field, shown in a plan view, each individual point represents the position of a single heliostat in north-south direction and east-west direction. The origin of the coordinate system is defined by the position of the center of the receiver 2710, here represented by a larger non-scale point.

aufgestellt, wie aus der Draufsicht in Fig. 27 ersichtlich. Die Reflektorflächendichte

des gesamten Heliostatenfeldes ist somit gleich der maximalen Reflektorflächendichte

im Heliostatenfeld.The heliostat 2790 are in the entire heliostat field at regular intervals to each other with the maximum reflector surface density

placed as seen from the top in Fig. 27 seen. The reflector surface density

of the entire heliostat field is thus equal to the maximum reflector surface density

in the heliostat field.

In the east-west direction the heliostats are placed in the heliostat field with distances A _OW of 2.75 m, ie there is a gap Z _OW of 0.5 m between the reflectors with width B _Hel of 2.25 m, if these are in the horizontal parking position, in which the reflectors are horizontal and the long side of the heliostats oriented in north-south direction, as in the plan view in Fig. 17 shown.

The high deployment density within the East-West series of approximately 82% (= 2.25 m / 2.75 m) is possible through the use of heliostats with fixed horizontal axis suspension (FHA), as in WO 02/070966 A1 . WO 2008/092194 A1 and WO 2008/092195 A1 be-written.

In the north-south direction, the heliostat series are set up in the near field with distances A _NS of 4.21 m, ie there is one each between the reflectors with the length L _Hel = 3.21 m (and therefore 3.21 m wide rows) Space Z _NS of 1.0 m when in horizontal parking position. Please refer Fig. 17 , The setup density of the rows can in principle also be higher if the heliostat rows each have a half heliostat spacing A _OW (cf. Fig. 17 ) are offset, as in Fig. 10 shown.

62%The combination of the setup density in the east-west and in the north-south results in a constant reflector surface density in the heliostat field ${\mathrm{\rho }}_{\mathrm{Max}}=\mathrm{ca}\mathrm{,}$

62%

In contrast to design example 1, this heliostat field consists exclusively of a near field with heliostats at constant distances from each other.

The entire heliostat field extends in north-south direction from about 38 m north of the receiver 2710 to 17 m south of the receiver 2710 and in east-west direction from 33 m east of the receiver to 33 m west of the receiver 2710.

The scope of the heliostat field is described in Fig. 27 in about a circular shape. The center of the Heliostatenfeldes lies approx. 10 m north of the receiver 2710, as from in Fig. 27 drawn scale information is visible. The receiver 2710 is shifted about 10 meters from the center of the field to the south. The diameter of the heliostat field is approx. 60 m and thus approx. 1.3 x H _R.

The heliostat field is continuously continuous.

Summary of the essential features of exemplary embodiment 3

• Receiver height H _R : 45 m above heliostat field.
• Area of the receiver aperture: 3 mx 6 m = 18 m ² .

• Tragstruktur: Turmdrehkran, bestehend aus einer vertikalen Tragstruktur 2621 und einem Ausleger 2622 für hängend montierten Receiver 2610 und mit Fußpunkt nördlich vom Heliostatenfeld.
• Heliostatenfeld mit konstanter Reflektorflächendichte
  
  entspricht der maximalen Reflektorflächendichte
  
  von ca. 71%.
  1. 1. Heliostaten mit fester Horizontalachsen-Aufhängung für hohe Aufstelldichte innerhalb einer Reihe in Ost-West-Richtung.
  2. 2. Heliostatenfeld mit Reflektorflächendichte $\mathrm{\varrho }={\mathrm{\varrho }}_{\max }={\mathrm{\varrho }}_{\mathrm{Gesamt}}=68\%>\mathrm{60}\%\mathrm{.}$
     
  3. 3. Heliostatenfeld, das sich in Nord-,Ost-, Süd- und West-Richtung um den Receiver erstreckt und eine kontinuierlich durchgehende (ununterbrochene) Fläche darstellt.
• Kein Fernfeld.
• Reflektorflächendichte für das gesamte Heliostatenfeld
  
  beträgt ${\mathrm{\varrho }}_{\mathrm{Gesamt}}=\mathrm{\varrho }={\mathrm{\varrho }}_{\max }=68\%\mathrm{.}$
  

Receiver orientation: Normal vector of the aperture surface of the receiver 2710 directed vertically downwards, as in Fig. 15 and Fig. 26 shown.

• Support structure: Tower crane, consisting of a vertical support structure 2621 and a boom 2622 for suspended receiver 2610 and with base north of the heliostat field.
• Heliostat field with constant reflector surface density
  
  corresponds to the maximum reflector surface density
  
  of about 71%.
  1. 1. Heliostats with fixed horizontal axis suspension for high deployment density within a row in east-west direction.
  2. 2. Heliostat field with reflector surface density $\mathrm{\rho }={\mathrm{\rho }}_{\mathrm{Max}}={\mathrm{\rho }}_{\mathrm{total}}=68\%>\mathrm{60}\%\mathrm{,}$
     
  3. 3. Heliostat field extending around the receiver in the north, east, south and west directions, representing a continuous (uninterrupted) area.
• No far field.
• Reflector surface density for the entire heliostat field
  
  is ${\mathrm{\rho }}_{\mathrm{total}}=\mathrm{\rho }={\mathrm{\rho }}_{\mathrm{Max}}=68\%\mathrm{,}$
  

Approach for the interpretation of the embodiments 1 to 3

For the design of the preceding embodiments 1 to 3, the following procedure has been selected in four preferably successive steps:

1. a) wobei im ersten Schritt eine Aufstellung der Heliostaten (1790; 1290, 1390) für ein Nahfeld (1636; 2236) auf einer vorzugsweise ebenen Gesamtgrundfläche definiert wird, das eine Reflektorflächendichte ρ von ρ > 60% aufweist,
   • wobei die Reflektorflächendichte ρ als Verhältnis aus der gesamten Reflektorfläche einer Region des Heliostatenfeldes zur überbauten Grundfläche derselben Region des Heliostatenfeldes definiert ist,
   • wobei jeder Heliostat einen um zwei Drehachsen (792, 793; 992, 993) verstellbaren Reflektor (795; 995) aufweist, der die solare Strahlung auf die Zielfläche eines oder mehrerer Receiver (1610; 2210) bei sich ändernden Sonnenstand reflektiert,
   • wobei die Zielfläche eine Apertur (1511; 2011) bzw. ein thermischer Absorber (2015) bzw. ein photovoltaischer Absorber (2015) des jeweiligen Receivers ist (Fig. 15; Fig. 20),
   • wobei bei jedem Heliostaten die erste Drehachse (992; 1292, 1392) parallel zu der Aufstellfläche ausgebildet ist (Fig. 9; Fig. 12, Fig. 13) und eine Gruppe von Heliostaten mit einer gemeinsamen Aufstellfläche in einer Reihe aufgestellt sind, so dass die erste Drehachse (992; 1292, 1392; 1792) der Heliostaten (1290, 1390; 1790) in der jeweiligen Gruppe auf einer Linie liegen, d.h. miteinander fluchten,
   • wobei der Reflektor (995; 1295, 1395; 1795)jedes Heliostaten rechteckförmig ausgebildet ist und in Richtung der zweiten Drehachse (993; 1293, 1393) bevorzugt länger ist als in die dazu senkrechten Richtung und
2. b) wobei die gemeinsame Aufstellfläche einer oder mehrerer Gruppen von Heliostaten (1283; 1383) zur Gesamtgrundfläche jeweils um einen von der Position zum Receiver abhängigen Winkel α (Fig. 12) geneigt sein kann,
   • wobei im zweiten Schritt die Positionen der Heliostaten mit dem Abstand vom Receiver (1610; 2210) bestimmt werden, wobei berechnet wird, wie weit das Nahfeld (1636; 2236) mit gleicher Reflektorflächendichte ρ um den Receiver herum reicht und
   • wo das Fernfeld (1638; 2238)anschließend an das Nahfeld beginnt,
   • wobei im Fernfeld die Abstände in Ost-West-Richtung bzw. Nord-Süd-Richtung vergrößert werden müssen, um das gegenseitige Blockieren der Heliostaten weitgehend zu vermeiden bzw. gering zu halten,
   • wobei Blockieren bedeutet, dass ein Heliostat den Strahlengang vom Reflektor eines benachbarten Heliostaten zur Zielfläche des Receivers mindestens teilweise abdeckt,
3. c) wobei im dritten Schritt die Strahlungsleistung, die die jeweiligen Heliostaten auf die Zielfläche des Receivers (1610; 2210) transferieren, berechnet wird und bevorzugt diejenigen Heliostaten für das Heliostatenfeld ausgewählt werden, die zum Auslegungszeitpunkt oder anderen bestimmten Zeitpunkten oder Zeiträumen den höchsten Beitrag zur Strahlungsleistung auf der Zielfläche des Receivers leisten,
   • wobei das Heliostatenfeld mindestens aus einem Nahfeld und, je nach erforderlicher Strahlungsleistung auf der Zielfläche des Receivers, auch aus einem Fernfeld gebildet wird,
   • wobei, sofern eine Receiverhöhe H_R von mindestens 100 m gewählt wird, ein Fernfeld vorgesehen wird und der größte Durchmesser D_H des Heliostatenfeldes verzugsweise weniger als das Sechsfache der Receiverhöhe H_R beträgt,
   • wobei im vierten Schritt eine Tragstruktur (Fig. 14) ausgewählt wird, die geeignet ist, den Receiver (1410) in der definierten Position über dem Heliostatenfeld zu halten, wobei diese Tragstruktur ausgebildet ist als
     1. i. ein Bogen (Fig. 14a),
     2. ii. oder ein Sprengwerk (Fig. 14b)
     3. iii. oder eine abgehängte Seilkonstruktion (Fig. 14c),
        • wobei diese drei Tragstrukturen, i, ii und iii, mit jeweils mindestens zwei Fußpunkten, die sich bevorzugt im Außenbereich oder außerhalb des Heliostatenfeldes befinden,
     4. iv. oder ein kranförmiges Tragwerk (Fig. 14d) mit einem den Receiver (1410) tragenden Ausleger bzw. Kragarm(1422), der sich über das Heliostatenfeld erstreckt,
        • wobei ein oder mehrere Fußpunkte des kranförmigen Tragwerks sich entweder im Außenbereich oder bevorzugt außerhalb des Heliostatenfeldes auf der vom Äquator abgewandten Seite des Receivers befinden,
        • wobei die Position eines am Ausleger (2622, 2722) montierten Receivers (2610, 2710) in bis zu drei Dimensionen veränderbar sein kann,
        • so dass für das im dritten Schritt bestimmte Heliostatenfeld verschiedene Positionen für den Receiver für bestimmte Sonnenstände gewählt werden, um den Wirkungsgrad des Heliostatenfeldes für die jeweiligen Sonnenstände zu erhöhen (Fig. 26, Fig. 27).

Method for designing a heliostat field of a solar central receiver system,

1. a) wherein, in the first step, a list of the heliostats (1790, 1290, 1390) for a near field (1636, 2236) is defined on a preferably flat overall base area having a reflector surface density ρ of ρ> 60%,
   • wherein the reflector surface density ρ is defined as the ratio of the total reflector area of a region of the heliostat field to the superstructured base area of the same region of the heliostat field,
   • wherein each heliostat has a reflector (795; 995) adjustable about two axes of rotation (792, 793; 992, 993) which directs the solar radiation towards the target surface of one or more Receiver (1610; 2210) reflected in changing position of the sun,
   • wherein the target surface is an aperture (1511; 2011) or a thermal absorber (2015) or a photovoltaic absorber (2015) of the respective receiver (2015) Fig. 15 ; Fig. 20 )
   • wherein for each heliostat the first axis of rotation (992, 1292, 1392) is parallel to the footprint ( Fig. 9 ; Fig. 12 . Fig. 13 ) and a group of heliostats are placed in a row with a common footprint so that the first axis of rotation (992; 1292, 1392; 1792) of the heliostat (1290, 1390; 1790) in the respective group are in line, ie, together aligned,
   • wherein the reflector (995; 1295, 1395; 1795) of each heliostat is rectangular in shape and is preferably longer in the direction of the second axis of rotation (993; 1293, 1393) than in the direction perpendicular thereto and
2. b) wherein the common set-up area of one or more groups of heliostats (1283; 1383) relative to the total base area in each case by an angle α dependent on the position to the receiver ( Fig. 12 ) may be inclined
   • wherein in the second step, the positions of the heliostats are determined with the distance from the receiver (1610; 2210), wherein it is calculated how far the near field (1636; 2236) with the same reflector surface density ρ reaches around the receiver, and
   • where the far field (1638; 2238) begins after the near field,
   • in the far field, the distances in the east-west direction and north-south direction must be increased in order to largely prevent or keep the mutual blocking of the heliostats,
   • wherein blocking means that a heliostat at least partially covers the beam path from the reflector of an adjacent heliostat to the target surface of the receiver,
3. c) wherein, in the third step, the radiant power which the respective heliostats transfer to the target surface of the receiver (1610; 2210) is calculated and preferably those heliostat data are selected for the heliostat which at the design time or other particular times or periods has the highest contribution to Radiate power on the target surface of the receiver,
   • wherein the heliostat field is formed at least from a near field and, depending on the required radiation power on the target surface of the receiver, also from a far field,
   • wherein, if a receiver height H _R of at least 100 m is selected, a far field is provided and the largest diameter D _{H of} the heliostat field is preferably less than six times the receiver height H _R ,
   • wherein in the fourth step a supporting structure ( Fig. 14 ), which is suitable for holding the receiver (1410) in the defined position above the heliostat field, this support structure being designed as
     1. i. a bow ( Fig. 14a )
     2. ii. or an explosive device ( Fig. 14b )
     3. iii. or a suspended rope construction ( Fig. 14c )
        • these three support structures, i, ii and iii, each with at least two base points, which are preferably located in the outer area or outside the heliostat field,
     4. iv. or a crane-shaped structure ( Fig. 14d ) with a cantilever (1422) supporting the receiver (1410) which extends over the heliostat field,
        • wherein one or more bases of the crane-shaped structure are located either on the outside or preferably outside the heliostat field on the side of the receiver facing away from the equator,
        • wherein the position of a receiver (2610, 2710) mounted on the boom (2622, 2722) can be variable in up to three dimensions,
        • so that for the heliostat field determined in the third step, different positions for the receiver for certain positions of the sun are selected in order to increase the efficiency of the heliostat field for the respective position of the sun ( Fig. 26 . Fig. 27 ).

The following definitions are used in the application.

definitions:

Heliostat with fixed quasi-polar axis suspension (FQA): A heliostat with FQA is a heliostat in which the first fixed axis of rotation is parallel to a footprint which in turn is tilted by an angle α to the total base area.

Group of Heliostats: Is a variety of heliostats with FQA the one common footprint and a common first axis of rotation both have an angle α to the total base area.

Module: A plurality of groups of heliostats, which all have a common footprint and parallel first axes of rotation are combined to form a module and are held by a common support system of support frame and legs. Surface: The footprint of a heliostat is a freely defined reference surface to which the first axis of rotation of the heliostat is fixed.

First axis of rotation : The first axis of rotation is one of the two axes of rotation of the heliostat, with the first axis of rotation in relation to the footprint.

Second axis of rotation: The second axis of rotation is one of the two axes of rotation of the heliostat, wherein the second axis of rotation is fixed with respect to the reflector.

Normal vector of the receiver: The normal vector n _{R of} the receiver is the surface normal vector of the target surface of the receiver.

Receiver width : The receiver width is the width of the target area of the receiver or the side length of the target area in the case of a rectangular target area.

Shadowing : When heliostats are shadowed in the heliostat field, this means that a heliostat at least partially covers the beam path from the sun to the reflector of an adjacent heliostat.

Blocking: When heliostat blocks in the heliostat field, it means that a heliostat at least partially covers the beam path from the reflector of an adjacent heliostat to the target surface on the receiver.

Design time: The design time is the time at which a solar central receiver power plant is designed and the performance of the system, as well as the radiation power on the target surface of the receiver are defined. Typically, the interpretation time is on the day of the summer solstice (June 21 in the northern hemisphere) at 12 noon, solar time.

Heliostat : A heliostat is a two-axis adjustable reflector that reflects solar radiation to a target or target surface. The biaxial tracking ensures that the target point or the target surface are continuously irradiated in a daytime changing sun position, wherein the heliostat has a first axis of rotation and a first perpendicularly arranged second axis of rotation, which is arranged on a footprint, wherein the first Rotary axis with respect to the footprint and the second axis of rotation with respect to the reflector are fixed. The reflector of the present invention has a rectangular shape, wherein the shorter edge length is referred to as width B _Hel and the longer edge length as length L _Hel . Thus, the rectangular reflector has the reflector surface F _Hel = B _Hel x L _Hel .

Fixed Horizontal Axis Heliostat : A heliostat with fixed horizontal axis suspension is a heliostat with two axes arranged perpendicular to each other, with the first axis horizontally and fixedly arranged, around which the second axis moves. In the present invention, a heliostat is used with such a horizontal axis suspension, as described in detail in WO 2008/092194 A1 . WO 2008/092195 A1 as in WO 02/070966 A1 and described in [8].

Heliostat field : A heliostat field is a field formed from a multiplicity of heliostats, which reflects the solar radiation on a target point or a target surface of a receiver, whose principle for example from the US Pat. No. 4,172,443 respectively. US 4,220,140 known, see also the extracted from it Fig. 1 respectively. Fig. 5 ,

Receiver : A receiver is a system that converts solar radiation into heat or, if it is a photovoltaic receiver, directly into electricity. The heat from a thermal receiver is fed to a heat transfer medium, which may include water, water vapor or air. The receiver is typically located at the destination of the heliostat field. The principle of a receiver, for example, from the US Pat. No. 4,172,443 respectively. US 4,220,140 known, see also the extracted from it Fig. 1 respectively. Fig. 5 ,

Cavity Receiver : As in Fig. 15a 1, a cavity receiver is a receiver in which the solar radiation absorbing surface, the absorber 1515, is located within a cavity 1512. The radiation succeeds through the aperture 1511 into the cavity. The principle of such a cavity receiver, for example, from the patent US 4,220,140 respectively. WO 2008/153922 A1 and from [9] known.

Absorber: The absorber is the part of the receiver on which the solar radiation strikes and converts it in the case of a thermal absorber into heat and dissipated to a heat transfer medium, such as from the US patent US 4,220,140 known or in the case of a photovoltaic absorber consists of photovoltaic cells which convert the solar radiation directly into electricity.

Receiver with external absorber : A receiver with external absorber is a receiver in which the absorbing surface is part of the outer surface of the receiver, for example, the outer surface of a cylindrical receiver, as in the US patent specification US 4,172,443 known from the the Fig. 1 has been removed, showing the cylindrical surface of the receiver 110, or in Fig. 15b and Fig. 20b in which the absorber 1515/2015 is located on an outside of the receiver.

Aperture: The aperture is the optical entrance opening of a cavity receiver, such as from [9] the WO 2008/153922 A1 known and in Fig. 15 to see.

Target area: Depending on the type of receiver, the aperture, the thermal absorber or the photovoltaic absorber may be the target surface of the receiver.

aufweist. Das heißt, dass die Heliostaten in gleichbleibenden Abständen zueinander aufgestellt sind. Ein Heliostatenfeld kann auch ausschließlich aus einem Nahfeld bestehen. Near field : In the present invention, the near field of a heliostat field is defined as the portion of the heliostat field extending below the receiver and a constant reflector surface density

having. This means that the heliostats are set up at constant intervals. A heliostat field can also consist exclusively of a near field.

mit größer werdendem horizontalen Abstand vom Receiver abnimmt. Ein Heliostatenfeld kann auch ausschließlich aus einem Fernfeld bestehen. Far field : The far field of a heliostat field is defined as the part of the heliostat field that completely or partially surrounds the receiver with a certain horizontal distance and at which the reflector surface density

decreases with increasing horizontal distance from the receiver. A heliostat field can also consist exclusively of a far field.

Reflector surface: The reflector surface is the surface F _{Hel of} the reflector of a single heliostat.

: Die Reflektorflächendichte

ist das Verhältnis der Reflektorfläche einer Region des Heliostatenfeldes zur Grundfläche dieser Region des Heliostatenfeldes. Reflector surface density

: The reflector surface density

is the ratio of the reflector area of a region of the heliostat field to the base area of this region of the heliostat field.

: Die maximale Reflektorflächendichte

entspricht dem höchsten Wert der im gesamten Heliostatenfeld vorkommenden Reflektorflächendichte. Maximum reflector surface density

: The maximum reflector surface density

corresponds to the highest value of the reflector surface density occurring in the entire heliostat field.

: Die gesamte Reflektorflächendichte

ist das Verhältnis der Reflektorfläche des gesamten Heliostatenfeldes zur Grundfläche des gesamten Heliostatenfeldes. Total reflector surface density

: The total reflector surface density

is the ratio of the reflector area of the entire heliostat field to the base area of the entire heliostat field.

Heliostat width : The heliostat width is the width B _{Hel of} the rectangular reflector of the heliostat and is at the present Invention, as in Fig. 17 shown, always smaller than the length L _{hel of} the reflector.

Heliostat Length: The heliostat length corresponds to the length L _Hel of the heliostat's rectangular reflector and is in the invention described herein, as in Fig. 17 shown, always greater or equal to the width B _{hel of} the reflector.

Heliostat series: series of heliostats, where the heliostats as in Fig. 17 shown in a line with the first axis of rotation, the fixed horizontal axis 1792 of the heliostats with fixed horizontal axis suspension, are placed.

Setup density within a heliostat series : The setup density within a heliostat series is the ratio of the width B _{Hel of} the reflector of the heliostat to the distance A _{OW of} two adjacent heliostats within a row. Here, the distance A _{OW of} two adjacent heliostats is defined as the distance of the centers of two adjacent reflectors of these heliostats, as in Fig. 17 shown.

Setup density of heliostat series : The setup density of heliostat series is as in Fig. 17 shown, the ratio of the width of the heliostat series, which is equal to the length L _{Hel of} the reflectors of the heliostat, to the distance A _NS two adjacent heliostat series, wherein the distance between two adjacent heliostat series is defined as the distance of the centers of the two adjacent heliostat series.

Diameter of a heliostat field D _H : The diameter D _{H of} a heliostat field becomes, as in the Fig. 2 . 3 . 4 and 6 shown as the distance, the most distant heliostat.

Receiver height H _R : The receiver height H _R is as in Fig. 1 Shown as defined as the vertical distance of the center of the absorber surface of a receiver with external absorber or the receiver aperture of a cavity receiver from the plane defined by the centers of the reflectors of the heliostat of the heliostat field. The receiver height is used as a unit size at which other sizes, such as the heliostat field size, are sized.

references

• [1] Winter, C.-J .; Sizmann, RL; Vant-Hull, LL: Solar Power Plants, Berlin, Heidelberg, New York: Springer, 1991
• [2] Burgalet, JI; Arias, S; Salbidegoitia IB, Operational advantage of a central tower with thermal storage system. In SolarPACES 2009, Conference Proceedings, 1.-18. September 2009, Berlin, Germany, ISBN 978-3-00-028755-8
• [3] Gould, B .: Molten Salt Power Towers, Presentation at DOE Program Review, Austin, Texas April 23, 2008
• [4] Koll, G .; Schwarzbözl, P .; Hennecke, K .; Hartz, T .; Schmitz, M .; Hoffschmidt, B .; The solar tower Jülich - A research and demonstration plans for central receiver systems. in SolarPACES 2009 Conference Proceedings, ISBN 978-3-00-028755-8
• [5] Abengoa Solar SA, White Paper on Solar Tower Technologies, Downloaded on 19.8.2010 by www.abengoasolar.com by Abengoa Solar SA, based in Avda de la Buhaira 2, 48018 Seville, Spani s
• [6] www.esolar.com by eSolar Inc., located at 130 West Union Street, Pasadena, CA 91103, USA
• [7] Steve Schell, Design and Evaluation of eSolar's Heliostat field, in SolarPACES 2009 Conference Proceedings, 1.-18. September 2009, Berlin, Germany, ISBN 978-3-00-028755-8
• [8th] Schramek, P. and Mills, DR; Heliostat for maximum ground coverage; Energy 29; 2004; 701-713
• [9] Buck, R .; Bräuning, T .; Thinks.; Pfänder, M .; Schwarzbözl, P .; Téllez, F; Solar hybrid gas turbine-based power tower Systems (REFOS); Journal of Solar Energy Engineering, Vol. 124, February 2002; pp. 2-9
• [10] Liebherr, data sheet tower crane 132 EC-H8 FR.tronic, 132 EC-H8 Litronic. Liebherr-Werk Biberach GmbH, Biberach an der Riss. www.liebherr.com

LIST OF REFERENCE NUMBERS

10

Receiver

11

Apertur

12

Hohlraum

13

Glaskuppel

15

Absorber

17

Einlass des Wärmeträgermediums

18

Auslass des Wärmeträgermediums

20

Tragstruktur

21

vertikale Tragstruktur/Turm

22

Ausleger oder Kragarm

23

Fußpunkt

24

Abspannseil

30

Heliostatenfeld

31

Nordfeld

32

Südfeld

34

Heliostatenfeldaussparung

36

Nahfeld

37

Äußere Grenze des Nahfeldes

38

Fernfeld

39

Äußere Grenze des gesamten Heliostatenfeldes

80

Modul eines FQA Heliostaten

83

Gruppe von Heliostaten

85

Rahmen

87

Beine

90

Heliostat

91

Tragrahmen

92

Erste mit Aufstellfläche fest verbundene Drehachse

93

Zweiter mit Reflektor fest verbundene Drehachse

94

Mechanische Koppelung der Nachführung der zweiten Drehachse

95

Reflektor

99

Raumvolumen in dem der Reflektor sich frei bewegen kann

In the drawings, the same reference numerals are used in the figures for the same fact, and when the last two final digits of the reference numerals are the same, similar facts are presented, which are listed below only the last two final digits. The numbers in front of the two final digits indicate the number of the respective figure.

10

receiver

11

aperture

12

cavity

13

glass dome

15

absorber

17

Inlet of the heat transfer medium

18

Outlet of the heat transfer medium

20

supporting structure

21

vertical support structure / tower

22

Boom or cantilever

23

nadir

24

guy rope

30

Heliostat field

31

Nordfeld

32

Südfeld

34

Heliostat field recess

36

near field

37

Outer limit of the near field

38

far field

39

Outer limit of the entire heliostat field

80

Module of a FQA heliostat

83

Group of heliostats

85

frame

87

legs

90

heliostat

91

supporting frame

92

First axis of rotation firmly connected with the footprint

93

Second fulcrum fixed to the reflector

94

Mechanical coupling of the tracking of the second axis of rotation

95

reflector

99

Room volume in which the reflector can move freely

Claims (17)

1. Central receiver solar system with a heliostat field, consisting of

   a) one or more receivers (110),

   b) a plurality of heliostats (190), forming the heliostat field (130), which are arranged on a preferably level overall ground surface, wherein each heliostat has a reflector (795; 995) that can be moved about two rotary axles (792, 793; 992, 993), which reflects the solar radiation onto the target surface of the one or more receivers during changing position of the sun, wherein the target surface is configured as an aperture (1511; 2011) or a thermal absorber (2015) or a photovoltaic absorber (2015) of the respective receiver,
   wherein each heliostat has a first rotary axle and a second rotary axle perpendicular to the first rotary axle and is arranged on a mounting surface,
   wherein the first rotary axle (792; 992) is rigidly arranged relative to the mounting surface and the second rotary axle (793; 993) relative to the reflector (795; 995), and

   c) a support structure (120), on which the one or more receivers (110) are secured above the heliostat field (130),

   d) the heliostat field is formed with parallel rows of heliostats,

   e) the first rotary axle (992; 1292, 1392) for each heliostat is oriented parallel to the mounting surface

   f) heliostats with a common mounting surface are arranged in a row, so that the first rotary axle (1292, 1392; 1792) of the heliostats in the respective group lie on the same line, i.e., are aligned with each other,

   g) each reflector (995; 1295, 1395; 1795) is rectangular in configuration,
   characterized in that,

   h) the support structure for the receiver is configured as a support structure reaching across the heliostat field,

   i) the normal vector of the target surface of the receiver is pointed downward, preferably perpendicular, at the heliostat field

   j) the heliostat field has a near field (1636; 2236) underneath the receiver, which as a reflector surface density ρ of ρ > 60%, where the reflector surface density ρ is defined as the ratio of the the overall reflector surface of a region of the heliostat field to the built-over ground surface of the same region of the heliostat field, and the reflector is preferably longer in the direction of the second rotary axle (993; 1293, 1393) than in the direction perpendicular to this.
2. Central receiver solar system according to claim 1, characterized in that in the near field (1636; 2236) the spacings of neighboring heliostats within each row have a predetermined first spacing and the spacings of neighboring rows have a predetermined second spacing from each other in the direction perpendicular to this.
3. Central receiver solar system according to claim 1 or 2, characterized in that the rows of the heliostat field are oriented in the east-west direction or the rows of the heliostat field are oriented in the north-south direction.
4. Central receiver solar system according to claim 1, characterized in that the common mounting surface of one or more groups ofheliostats (1283; 1383) is inclined to the overall ground surface each time by an angle α, dependent on the position to the receiver, while a number of groups of heliostats with common mounting surface and with parallel first rotary axles in a row perpendicular to the first rotary axle are assembled into a module (1280, 2180, 2380, 2480) and several modules are assembled into a module row (2181, 2381; 2481).
5. Central receiver solar system according to claim 1 and 4, characterized in that in the near field, the heliostat field underneath the receiver, the spacings of neighboring groups ofheliostats (2383) within each module (2380) each time have a predetermined first spacing and the spacing of neighboring module rows (2181, 2381) in the direction perpendicular to this have a predetermined second spacing from each other.
6. Central receiver solar system according to claim 1 and one of claims 2 to 5, characterized in that the first rotary axle of the group ofheliostats (1283, 1383) is mechanically coupled so that the heliostats (1290, 1390) have a common rotary axle.
7. Central receiver solar system according to claim 1 and one of claims 2 to 6, characterized in that the support structure for the receiver extends as an arch across the heliostat field, wherein two or more footpoints of the arch are preferably located in the outer region or outside the heliostat field.
8. Central receiver solar system according to claim 1 and one of claims 2 to 6, characterized in that the support structure for the receiver extends as a truss, i.e., a triangular frame, across the heliostat field, wherein two or more footpoints of the truss are preferably located in the outer region or outside of the heliostat field.
9. Central receiver solar system according to claim 1 and one of claims 2 to 6, characterized in that the support structure for the receiver extends as a suspended cable construction across the heliostat field, wherein two or more footpoints of the suspended cable construction are located preferably in the outer region or outside of the heliostat field.
10. Central receiver solar system according to claim 1 and one of claims 2 to 6, characterized in that the support structure for the receiver extends across the heliostat field as a cranelike support system with a jib or cantilever arm supporting the receiver, wherein one or more footpoints of the cranelike support system are located either in the outer region or preferably outside of the heliostat field on the side of the receiver facing away from the equator.
11. Central receiver solar system according to claims 1 and 10, characterized in that the jib (2622, 2722) of the cranelike support structure can turn about the vertical axis, so that the positions of the receiver (2610, 2710) can be changed, the receiver is preferably arranged able to move along the jib (2622, 2722) of the cranelike support structure, so that the position of the receiver (2610, 2710) can be additionally changed, and preferably the height of the receiver (2610, 2710) is arranged to be changeable.
12. Central receiver solar system according to claim 1 and one of claims 2 to 11, characterized in that the support structure carries the receiver in a suspended arrangement on its bottom side facing the heliostat field.
13. Central receiver solar system according to claim 1 and one of claims 2 to 12, characterized in that the heliostat field extends in the north, east, south and west direction underneath and around the receiver, forming a continuous heliostat field throughout.
14. Central receiver solar system according to claim 1 and one of claims 2 or 3 or one of claims 6 to 13, characterized in that the heliostat field in addition to the near field has a far field (1638), in which the spacings between the heliostats increase in the east-west direction or north-south direction with increasing distance from the receiver.
15. Central receiver solar system according to claim 1 and one of claims 4 to 13, characterized in that the heliostat field in addition to the near field has a far field (2238), in which with increasing distance from the receiver the spacings between the module rows (2481) increase in the north-south direction or in the east-west direction the spacings between groups of heliostats (2483) within a module (2480) increase from one module to the next.
16. Central receiver solar system according to claim 1 and one of claims 2 to 15, characterized in that receiver height H_R is at least 100 and the largest diameter D_H of the heliostat field is preferably less than six times the receiver height H_R.
17. Method for the design of a heliostat field of a central receiver solar system according to one of claims 1 to 16, consisting of the following steps:

    a) wherein, in the first step, a setup of heliostats (1790; 1290, 1390) is defined for a near field (1636; 2236) on a preferably level overall ground surface, having a reflector surface density ρ of ρ > 60%,

    b) wherein the common mounting surface of one or more groups of heliostats (1283; 1383) can be inclined to the overall ground surface by an angle α dependent on the position to the receiver,

    • wherein in the second step the positions of the heliostats are determined with the distance from the receiver (1610; 2210), calculating how far the near field (1636; 2236) with the same reflector surface density ρ reaches around the receiver and

    • where the far field (1638; 2238) then begins at the near field,

    • wherein in the far field the distances in the east-west direction and north-south direction must be increased to prevent or reduce the mutual blocking of the heliostats as much as possible,

    • wherein blocking means that a heliostat at least partly covers the beam path from the reflector of an adjacent heliostat to the target surface of the receiver,

    c) wherein in the third step the radiation power which the respective heliostats transfer onto the target surface of the receiver (1610; 2210) is calculated and preferably those heliostats are chosen for the heliostat field that contribute at the designed time or other determined times the highest component to the radiation power on the target surface of the receiver,

    • wherein the heliostat field is formed at least by a near field and, depending on the required radiation power on the target surface of the receiver, also a far field,

    • wherein, if a receiver height H_R of at least 100 m is chosen, a far field is provided and the largest diameter D_H of the heliostat field is preferably less than six times the receiver height H_R,

    • wherein in the fourth step a support structure is chosen, which is suitable to holding the receiver (1410) in the defined position above the heliostat field, this support structure being configured as

    i. an arch,

    ii. or a truss,

    iii. or a suspended cable construction,

    • wherein these three support structures i, ii and iii, each with at least two footpoints that are preferably located in the outer region or outside the heliostat field,

    iv. or a cranelike support system with a jib or cantilever arm (1422) supporting the receiver (1410), which extends across the heliostat field,

    • wherein one or more footpoints of the cranelike support system is located either in the outer region or preferably outside of the heliostat field on the side of the receiver facing away from the equator,

    • wherein the position of a receiver (2610, 2710) mounted on the jib (2622, 2722) can be changed in up to three dimensions,

    • so that for the heliostat field determined in the third step different positions can be chosen for the receiver for particular positions of the sun in order to increase the efficiency of the heliostat field for the respective positions of the sun.

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